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The first sentence again

The very first sentence of the article states "Evolution (also known as biological or organic evolution) is the change..." - can this be changed to "The theory of evolution (also known as biological or organic evolution) is the change..." Thank you, Grantley 41.15.32.223 (talk) 19:58, 24 January 2011 (UTC)

This has been suggested many times. The motivation for the suggestion seems to normally be a wish to make evolution seem more like a thought and less like a factual description of how the world is. But there is consensus (in the scientific world) that evolution has occured and is happening. In Wikipedia the criterion is existence of authoritative sources for the information. The existence of evolutionary processes fullfills this criterion to a very high degree. --Ettrig (talk) 08:13, 25 January 2011 (UTC)

I agree with Ettrig, evolution is a thing, and the theory of evolution is another thing. Both things verifiably exist and are notable according to reliable sources.--Andrew Lancaster (talk) 13:04, 25 January 2011 (UTC)

Unfortunately your very statement shows that you are biased, and therefore the whole article is flawed - a fact is only a fact when a reliable source was there to witness the fact, or in science if the fact is repeatable. Evolution can do neither - it is therefore only a theory, amongst other possible theories like a extra-terristial visited here, or creation or something else. The mere fact that many believe this theory does not make it a fact, as a few hundred years ago many believed the earth flat did not make the earth flat. It may be a very plausible theory, but until proof exists, it remains a theory and if we call it by any other name we are not being scientific. 41.14.230.243 (talk) 16:25, 25 January 2011 (UTC)

See the FAQ Q5 for the answer to your claim. . . dave souza, talk 16:56, 25 January 2011 (UTC)

Read these two classic research articles [1][2]. One is by Richard Lenski's lab and the other is by John Endler's group. Evolution is a fact because it has been documented. mezzaninelounge (talk) 18:19, 25 January 2011 (UTC)

Read your articles - first one said a little less than nothing, second article is so old, it is no longer applicable. Maybe you should check up Encyclopedia Britanica "Evolution; Biological theory that animals and plants have their origin in other preexisting types and that the distinguishable differences are due to modifications in successive generations." Even the industry standard encyclopedia would not dare call evolution a fact - to date I have not seen one shred of undisputable evidence for evolution (and I have read extensively). Just like there is no undisputable evidence for any of the other theories. So are they all facts, or are they all theories? The moment you call a theory a fact, you have crossed the fine line of no longer having an open mind - please change the first sentence to reflect reality that evolution is a theory, maybe a very plausible one, but a theory nevertheless. —Preceding unsigned comment added by 41.19.167.243 (talk) 21:54, 26 January 2011 (UTC)

Sigh. mezzaninelounge (talk) 22:04, 26 January 2011 (UTC)

In other words, you're insisting that we replace the first sentence with the old Creationist canard of "it's just a theory, not a fact." Biological evolution, i.e., "descent with modification," has been observed, therefore it is a fact. The Theory of Evolution explains how and why biological evolution occurs. To state or even suggest that there is no evidence of biological evolution occurring is a bald-faced lie, no matter how many weasel words you stuff into it. Furthermore, if you were as extensively well read as you claim, you'd realize that a scientific theory EXPLAINS the HOW AND WHY of facts. And by demanding that we rephrase the opening sentence to state that evolution is a theory, not a fact, and that there is no evidence for evolution, or any other scientific theories, you have crossed the line by insisting that we put in deliberate falsehoods into the article.--Mr Fink (talk) 22:08, 26 January 2011 (UTC)

I agree with the last two posts. Please examine WP:SOAPBOX. Also consider WP:TRUTH which basically says that putting aside disputes between Wikipedia editors, we treat things as facts if reliable sources do in the mainstream literature of the fields involved. We are not here to make our cases. Because mainstream biological literature is unanimous, WP policy is very clear about how we should treat evolution. Arguments about what knowledge is and whether something called a theory is really knowledge are not for this talk page.--Andrew Lancaster (talk) 22:13, 26 January 2011 (UTC)

anon 41.xx... , read the FAQ at the top of this page. You will have to click where it says [show] a few times: once for the FAQ itself, once for Question 5, and once to see the references. Your statement that evolution can neither be witnessed nor repeated, and your words regarding "an open mind" amount to the sort of language used by intelligent design proponents and creationism apologists. Their arguments have been refuted myriads of times, and are not given weight in the encyclopedic scheme of things. Please sign your comments with four tildes thus: ~~~~ __ Just plain Bill (talk) 22:18, 26 January 2011 (UTC)

Species

For a very long time, this article had a sentence or two on an important shift in how natural scientists construed the concept "species." After a flurry of edits last week, this disappeared. I restored it, and another editor recently removed it again.

I think there is a major misunderstanding here. The concept "species" is not the same thing as "a species." "a separately evolving lineage that forms a single gene pool" refers to a group (even if of dynamic composition) of individuals. "the concpt of species" is a different thing altogether, it is about an idea, not an aggregate of organisms. As I understand it, much of the discussion last week was over how evolutionary biologists think of species meaning those collections of individual organisms that should be treated as belonging to a group, and how biologists think of such groups. I found the discussion edifying and have no problem with any of the changes made resulting from that discussion. But that discussion was not about the concept of species.

In my recent edit I did not mean to change any new content that resulted from that discussion.

But that discussion was not sufficient to delete content on a different matter that had been a part of the article for a long time. There is no reason that the article cannot include both points; they are not mutually exclusive or contradictory, they are just two different points. That is why I restored the deleted point. Slrubenstein | Talk 15:00, 24 January 2011 (UTC)

Yes, I missed that distinction. Now that I see it I find it unreasonable that we should have this much detail about the species concept in the article about evolution. The article is far too long. This passage is part of the cause. It should be moved to species concept, species, history of evolutionary thought and/or something similar. --Ettrig (talk) 16:12, 24 January 2011 (UTC)

I hardly think that one sentence is too long, or the reason for the great length of this article. As I said, I restored only material that had been cut in the past week. I added nothing. I know a great deal has been addd in the past week or two. I went to a great deal of effort to get this point down to one sentence - are you sure you have been as concise with your own points? Slrubenstein | Talk 16:37, 24 January 2011 (UTC)

We just had a large discussion on this above. The cited papers do not say that evolutionists see species as statistical phenomena alone - "Darwinian theory involves a shift away from viewing species as static ideal types, defined by the presence of a particular trait, to viewing them as populations with a history that requires more of a statistical approach for the analysis of multiple variable traits." - please read the discussion (here [3]) before modifying this section. Statistics is coupled with history in the cited papers - read the original sources. Moreover, there are now some errors in the way that this is written with information being duplicated that needs correction.Thompsma (talk) 00:28, 26 January 2011 (UTC)

I agree, the phrase "statistical phenomenon" is awkward and unconventional. It should be rephrased or removed. mezzaninelounge (talk) 00:34, 26 January 2011 (UTC)

Thompsma apparently does not know the difference between a thing (species, as a population with a history) versus a concept (species, meaning a particular way of thinking about things). We had a long discussion a year or two ago when this material was first introduced. The long discussion above is due almost entirely to Thompsm'a obtuseness and verbosity. Similarly, statistical phenomoenon is not unconventional, it is just a nominal phrase that refers to something other than statistics. Slrubenstein | Talk 15:12, 27 January 2011 (UTC)

Slrubenstein, I am not trying to be argumentative. It is just that I honestly never heard or read of species being referred to as a statistical phenomenon. I have however, heard of species being defined as either a taxonomic unit or as a concept [4]. Plus, I am confused by the statement that "a statistical phenomenon refers to something other than statistics." If that is the case, then I don't know how it could it be a statistical phenomenon. From what I know from statistics, everything is pretty much a statistical phenomenon, in that all phenomena (including those that can be reduced to equations) can be described or inferred using statistics. In other words, a statistical phenomenon is not unique to species. In summary, I am just a little confuse and my humble suggestion is that perhaps, there is another way or a simpler way of phrasing whatever it is that this statement is trying to convey. At the moment, I just don't quite understand it and I suspect other readers might be confused by it, which I am sure is not the intention. My two cents. mezzaninelounge (talk) 16:34, 27 January 2011 (UTC)

This is not the article about the concept of species, not even about species, not even about speciation. It is about evolution. Granted that speciation is an important subprocess of evolution, species is of secondary interest in this context. We need a simple and accessible explanation of what a species is, as a background for discussing speciation. Statistical phenomenon is not it. Very few will gain a better understanding from such an "explanation". I suggest we use Mayr's reproductive barrier, with a comment that this is but one of the definitions that have been used. The material about statistical models should not be just deleted but moved and copied to articles where it is more relevant. I also think it has to be elaborated to be understood by a normal reader. I also think the model should be characterized as probabilistic rather than statistic. --Ettrig (talk) 16:35, 27 January 2011 (UTC)

This is an article on evolution, and according to intellectual historians this shift in the meaning of the concept of species played a critical role in the rise of modern evolutionary theory. I know you are not trying to be argumentative, and I do not expect experts in biology also to be experts in intellectual history or the sociology of science. But these fields are relevant to the article on evolution too; NPOV is about including multiple views. Moreover, this article is written not just for evolutionary biologists, it is written for a wide an ddiverse audience, with different backgrounds and interests. The material comes from reliable sources, and has been in the article for some time; there is a tradition at Wikipedia of not deleting relevant content from reliable sources, and there are good reasons for this tradition. I see no point in quibbling over this. We are talking about one sentence that you happen not to find interesting. So? I am sure there are sentences you find compelling that many readers do not. You do not find "statistical phenomenon" clear but you think "population with a history" is; well, friend, some readers will find "statistical phenomenon" useful and "population with a history" unclear. But this does not mean I am vetoing a description of species as populations with histories, or however we decide to define them. Consensus does not require that every editor find every sentence in an article equally valuable - that would give any single editor veto power. Consensus is only possible when people can respect the fact that other editors have reasonable concerns, and when we agree to accept content that complies with our core policies (NPOV< V< and NOR), which this sentence does. What is important is the quality of the article as a whole and I do not see how this sentence detracts from it in any way. Slrubenstein | Talk 16:47, 27 January 2011 (UTC)

Slrubenstein, I'm with you. I don't think "population with history" is any better. I'm also not questioning the source. I am only suggesting that we make this sentence clearer. Regardless of the background of the reader, this sentence is just unclear. I would say the same thing if it was in an article on any subject ranging from physics, biology, chemistry, business, economics, psychology, philosophy, to statistics. It is not about POV or NPOV, it is just about being clear.

Here is what I am suggesting. This article already leans towards Mayr's Biological Species concept (BSC), which I think is perfectly fine. My suggestion would be to say that there are multiple concepts of species, one of which is the biological species concept. We then define it (it already is) and state that it is widely used and adopted. And then move on to the usual bits. That I believe would clear it up immediately.

I stumbled upon this sentence earlier and it did strike me as a little odd. I merely added my opinion here when you created a discussion section on it. Otherwise, I would not have written anything as my priority was to see if we could condense this article section by section to make it readable and easy to follow as previously discussed. mezzaninelounge (talk) 19:47, 27 January 2011 (UTC)

Well, anything can be improved upon. What I think is critical to communicate is that Europeans - not just natural scientists like Darwin, but the popular audience that read, argued about, and ultimately came to accept his seminal book - stopped viewing the "perfect" specimen of a particular species as representing an ideal, and started to view it merely as the average. This coincided with the general shift in the physical sciences from viewing the cosmos in mechanical terms to viewing it probabalistically (so that even the principle of inertia came to be formulated statistically). (And is tied to realizing that variation from the mean can actually be good, rather than a defect)

This is what one notable historian says:

Once our attention is redirected to the individual, we need another way of making generalizations. We are no longer interested in the conformity of an individual to an ideal type; we are now interested in the relation of an individual to the other individuals with which it interacts. To generalize about groups of interacting individuals, we need to drop the language of types and essences, which is prescriptive (telling us what finches should be), and adopt the language of statistics and probability, which is predictive (telling us what the average finch, under specified conditions, is likely to do). Relations will be more important than categories; functions, which are variable, will be more important than purposes; transitions will be more important than boundaries; sequences will be more important than hierarchies.

This shift results in a new approach to "species"; Darwin

concluded that species are what they appear to be: ideas, which are provisionally useful for naming groups of interacting individuals. "I look at the term species", he wrote, "as one arbitrarily given for the sake of convenience to a set of individuals closely resembling each other ... It does not essentially differ from the word variety, which is given to less distinct and more fluctuating forms. The term variety, again, in comparison with mere individual differences, is also applied arbitrarily, and for convenience sake."

It was a more general shift towards understanding natural laws and processes in terms of statistics and probabilities that made it possible for so many Europeans to find Darwin's arguments so plausible, not just the remarkable wieght of evidence. I do not think this merits more than one or two sentences in the article. If you can come up with a more elegant way to say it in a line, great. Slrubenstein | Talk 21:07, 27 January 2011 (UTC)

Got it. In other words, there was a movement away from essentialism towards a more group or population perspective on species. I thought that was what the 2nd and 3rd sentences might be getting at but I wasn't sure. I suggest we replace the second and third sentences with the following:

"During the pre-Darwinian era, the concept of species was essentialist, in that all entities within a species were viewed as fixed and immutable as they shared a common essence.[5][6] Such a view however, was replaced with post-Darwinian species concepts that viewed entities within a species as variable and intergrading units.[7] One of the prominent and widely used species concepts is Mayr's biological species concept, which states that a species ......"

What do you think? mezzaninelounge (talk) 21:29, 27 January 2011 (UTC)

I think it is well-written but still somewhat misses the point. de Moivre's Doctrine of Changes came out in the late 1700s, Gauss's monograph on statistics came out in 1809 I think. The point is that these works, and the revolution they were efecting in physics, as well as Malthus of course who applied statistics to human populations, were part of what pushed Darwin himself to abandon a Linnean understanding of species to the one you describe. What you wrote makes it sound as if people turned to a statistical approach because that is what fits with Darwin, as if Darwin is already the established authority. That is surely how Mayr viewed it, but to take Mayr's view as a historical accont of Darwin is anachronistic and bad history. When Darwin was writing, Darwin's species concept was not yet widely accepted. In other words, the point is not a pre-Darwinian and a post-Darwinian view (although this is a natural view of evolutionary biologists whose science all begins with stuff established largely after Darwin). The point is a pre-statistical view and a post-statistical view, because this is the historical context in which Darwin developed his ideas and people debated them before his view of "species" became established. Slrubenstein | Talk 21:51, 27 January 2011 (UTC)

Slrubenstein, I see what you're you saying. But the constraint of two sentences would not be able to do justice to all that. That kind of discussion would fit very well in the Science article, as you correctly pointed out, it includes not just species, but everything else in physics and astronomy. It would have wide applicability and generality there. So while I agree it is a valid point, I think it is a little too much info that may detract from our main purpose in the speciation section, which is to describe speciation.

I removed the part on "incompatibility with Darwinian views." I refined the suggested change again. All it says right now is describe the view before and after Darwin. It makes no further implications and it captures the statistical or population distribution point, albeit in a species or evolutionary context. mezzaninelounge (talk) 22:03, 27 January 2011 (UTC)

The more I look at the speciation section, the more I notice that this section is heavy on the concept of "species." I think the first four paragraphs can be condensed to two paragraphs or less. This is something we can all explore. mezzaninelounge (talk) 22:31, 27 January 2011 (UTC)

We should not allocate the needed space for analysis of the historical development of the species concept in the chapter on speciation. BUT, the change from an idealistic view of species to the more modern view was indeed a central pheomenon in the history of evolutionary thought, which is another chapter in this article. I would suggest that Slrubenstein describes this at some length in History of evolutionary thought and that we then collaborate to produce a more condensed variant in this article. Probabilistic phenomenon is not very explanatory. --Ettrig (talk) 11:21, 28 January 2011 (UTC)

Etrig, that sounds reasonable as well. Could you have a look at the suggested trimmed version of the first four paragraphs of the speciation section and let me know what you think? Based on your suggestion, we could even a couple more sentences from the trimmed version to the history section. Thanks. mezzaninelounge (talk) 15:14, 28 January 2011 (UTC)

I have no objection to moving this point to the history section. However, if it is moved to that section then the point, of putting Darwin's innovation in its historical context, is especially important. This can be accomplished through one sentence locating Darwin after a shift from a mechanical and deterministic view of nature to a statistical and probabalistic view of nature or words to this effect (with the citations currently provided to support this claim). I hope this is an acceptable compromise - to add this to messaninelounge's version AND to move it to the history section. That would be a good example of the kind of collaborative editing Wikipedia should be about. Slrubenstein | Talk 23:04, 28 January 2011 (UTC)

Suggested revision to first four paragraphs of speciation section

As discussed in Talk:Evolution#Species, there was a growing consensus that the opening statements of the Speciation section should be clearer. However, I am afraid that alone is not sufficient. The first four paragraphs of the speciation section is disproportionately devoted to defining and discussing the concepts and definitions of the word species. No doubt it is important, but it is overkill for this article, let alone in a section on speciation. I believe such lengthy discussions are best left to the species or speciation article. As with the current lead, I suggest that we trim the first four paragraphs of the speciation section as well as modify the phrasing of certain sentences. Here is a suggestion (bold letters represent new sentences, phrases, or words):

"Speciation is the process where a species diverges into two or more descendant species. Evolutionary scientists view the concept of "species" as a statistical phenomenon; this view is counterintuitive since the classical idea of species is still widely held, with a species seen as a class of organisms exemplified by a "type specimen" that bears all the traits common to this species. Instead, a species is now defined as a separately evolving lineage that forms a single gene pool. Although properties such as genetics and morphology are used to help separate closely related lineages, this definition has fuzzy boundaries.As with the concept of evolution, the concept of species itself has changed over time. During the pre-Darwinian era, the concept of species was essentialist, in that all entities within a species were viewed as fixed and immutable as they shared a common essence.[8][9] Such a view however, was replaced with post-Darwinian concepts of species that viewed entities within a species as variable and intergrading units.[10]

The term Species are defined in two ways,taxonomically and categorically can be defined as a unit of taxonomy or as a concept. Species are partitioned taxonmically into operational units for the practical application of framing When defined as a unit of taxonomy, it allows for the framing of evolutionary hypotheses in systematics. Systematicists study and analyze the morphological or genetic characters from different lineages and use parsimonious methods, such as cladistics or other statistical means to locate the position of the a taxon in the Linnean taxonomic hierarchy or biological classification. These methods create evolutionary trees that are can be used to infer, illustrate, test, or explain evolutionary relations, historical patterns, and phylogenetic transitions. "Systematics is one of the oldest scientific disciplines and, from its beginning, one of its central concepts has been the concept of species. Systematics can be characterized generally as the branch of science devoted to the study of the different kinds of organisms (biological diversity, in contemporary terms), and the term 'species' is Latin for 'kind.'" When a new species is discovered a type specimen and holotype specimens are usually deposited into a recognized or accredited academic institution, such as a museum, that serves as a taxonomic reference point.

Species are also defined categorically by critical natural forces that best explain the evolutionary mechanisms that are responsible for the crossing of the speciation threshold, from one species into two. In this context, the exact definition of a "species" is still controversial, particularly in prokaryotes, and this is called the species problem.

Unlike defining a species as a unit of taxonomy, there are multiple ways to defining a species as a concept. There is much diversity in life and varied biological reasons for speciation, which has resulted in more than twenty different kinds of species conceptsto facilitate the diverse modes, mechanisms, and evolutionary processes. The choice of which concept to use is dependent that is used is a pragmatic choice that depends on the particularities of the species concerned. For example, some species concepts may apply more readily toward sexually reproducing organisms and some while others lend themselves better toward asexual organisms. The Despite the diversity of various species concepts, these various concepts however, can be placed into one of three general broad philosophical approaches: 1) the interbreeding, 2) the ecological, and 3) the phylogenetic. The biological species concept (BSC) is a classic example of the interbreeding approach. Introduced by Ernst Mayr in 1942, the BSC states that "species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups". Despite its wide and long-term use, the BSC like others is not without controversy., particularly in prokaryotes, and this is called the species problem. Some researchers have attempted a unifying monistic definition of species, while others adopt a pluralistic approach and suggest that there may be a variety of different ways to logically interpret the definition of a what a species is."

Any constructive thoughts and feedback is most welcome. mezzaninelounge (talk) 00:24, 28 January 2011 (UTC)

I like the changes that you have suggested - it reads much better and it is a significant improvement.Thompsma (talk) 17:43, 28 January 2011 (UTC)

Thanks. Appreciate it. mezzaninelounge (talk) 18:11, 28 January 2011 (UTC)

Can I request you to omit the claim that pre-Darwinian species concepts were essentialist, a more recent study shows in considerable depth that it was much more complex than that, with a whole range of concepts preceding Darwin. Similarly, the BSC concept apparently long predated Mayr, though he was prominent in promoting its modern formulation. Am in the process of reading the book, and it will take me some time to get around to improving articles on the basis of it. Others with access to the book may be able to contribute, and it has been well recommended, the more impecunious may prefer to wait for the paperback anticipated to come out later this year. In the interim I can try to answer simple questions but can't put together an overview. . . dave souza, talk 18:16, 28 January 2011 (UTC)

Dave, what if we qualify it by saying that it was "predominantly essentialist?" Would that work better? Similarly, how about this on BSC: "The biological species concept (BSC) is a classic example of an interbreeding approach that was articulated and promoted by Ernst Mayr and other evolutionary biologists since 1942." mezzaninelounge (talk) 18:41, 28 January 2011 (UTC)

Taking the BSC first, in 1775 Blumenbach explicitly stated that interfertility is a test of species, so suggest changing "Introduced by Ernst Mayr in 1942,..." to "As defined by Ernst Mayr in 1942,...". The essentialist aspect is more complex, for example Ray saw variations within a species as "accidental variations" in Aristotle's sense, and not different species as long as they "spring from the seed of the same plant". Wilkins p. 127 summarises the pre-Darwinian early 19th century views as "while many naturalists were fixists, the leading criterion for species identification or explanation was derived from the descent of similar forms. Apart from Agassiz, nobody seems to have inferred, however, from fixism, or the pious form of creationism that was the usual form of words used, that species had essences or even that variation was firmly limited. In this period, variation was a real research difficulty." Cuvier's definition was widely disseminated, and "Linnaeus's almost taken as something too obvious, and a little overreligious, to mention." The prologue on p. 5 says that "Darwin and his successors did not add much to the species debate except to raise in sharp relief the problems brought about by the introduction of the notion of speciation and the subsequent mutability of classifications. Nevertheless, Darwin acts as a focal point for what follows..." So, we could say that there were various earlier ideas, and Darwin's work was pivotal in viewing varieties as incipient species in a process of speciation through common descent. . . dave souza, talk 22:20, 28 January 2011 (UTC)

I am for this change. I also think more should be removed. Much on systematics is about the use of the concept. This is not relevant to speciation. --Ettrig (talk) 21:09, 28 January 2011 (UTC)

I partly agree with Dave and partly quibble. The quibble: it is common in history that several people come up with an idea before, sometimes long before, it becomes established orthodoxy. That some people shared some of Darwin's ideas fitfty or more years before he proposed them is not the point; the point is that it was only after Darwin that many of these ideas were tied together and became the established paradign for biological research with wide acceptance among non-biologists. Now, where I agree: I think Dave is providing furthe evidence to support the point I have been arguing: that Darwin was not able to articulate his theory of evolution, and - just as important - a large audience was not ready to accept it - until certain other changes had occured in the way scientists viewed the universe. Valuing variation over the ideal; seeing phenomena in statistical terms (some kind of distribution, whether normal, bimodal, or other) are some of these ideas that others had to propose and demonstrate, before it could all come together for Darwin and, I repeat (because the history of the theory of evolution is not just the story of how some natural historians turned into evolutionary biologists, it is also the story of a public debate and public struggle to establish this view) a larger audience. This is the point made by historians like Menand, and it belongs in the article. It can be summed up in one or two sentences. I have no objection at all to placing it in the history section rather than the species section. Slrubenstein | Talk 23:15, 28 January 2011 (UTC)

It seems that there is a growing consensus that there is more to the history bit and that this history bit should be moved to the history section of this article. If that is the case, then I will remove those three sentences on the history bit from the suggested first four paragraphs of the speciation section. I will leave it to Slrugenstein or Dave Souza to take the lead on expanding the history bit. Thanks for the feedback and quibble. :) Have a good weekend. mezzaninelounge (talk) 03:05, 29 January 2011 (UTC)

I shortened the Speciation section of the article and left out the following text:

"As with the concept of evolution, the concept of species itself has changed over time. During the pre-Darwinian era, the concept of species was essentialist, in that all entities within a species were viewed as fixed and immutable as they shared a common essence.Such a view however, was replaced with post-Darwinian concepts of species that viewed entities within a species as variable and intergrading units."

Based on our discussions, I will leave it to Slrubenstein and/or Dave Souza to work these bits into the History section of the article.

No, if you delete material from the speciation section, you need to move it into the history section. I personally think the article is fine as is, so I see no reason why I should edit it. If you think it would be improved by moving somethinf grom speciation to the history section, well, you have made a reasonable case and as I said, I do not object. But it is for you to make the edit. Please do not delete content. if you delete material from the speciation section, please be sure to find a place to put it and the relevant citations in the history section. Thank you. Slrubenstein | Talk 23:57, 31 January 2011 (UTC)

Slrebenstein, it appears that we have a miscommunication here. I wrote in my last post prior to making that edit that I was planning on removing those three sentences from the history section and leave it to you and/or Dave to sort out and expand the history section as suggested by Ettrig. If you didn't like this arrangement, you could have clarified it with a short response. But you didn't, so I assumed your silence and your agreement to the move meant in principle, that you and/or Dave also agreed to make those changes yourself. Apparently, I misunderstood you and vice versa. So, I will reinsert those three sentences back into the speciation the next time I shorten it. But next time, try to relax. OK? There is no need to revert my edit and then post a terse response like the one above. If you wanted to keep those content in the speciation section for now, then all you had to do was either to reinsert the three sentences yourself OR politely ask me to do it for the time being. So in the future, assume good faith and talk to me first? I'm not going anywhere. mezzaninelounge (talk) 00:43, 1 February 2011 (UTC)

I did not respond earlier because I have been very busy. I was terse because i am very busy. Please know I am not now being rude. I appreciate your good intentions, your knowledge, and the improvements you have made to the article. I am just writing in between much more onerous and important commitments. As i said i have no objection to someone moving this material to the history section, but the person to move it should be somene who believes it is better suited to that section. Thanks, Slrubenstein | Talk 12:35, 1 February 2011 (UTC)

OK. I understand. mezzaninelounge (talk) 17:33, 1 February 2011 (UTC)

Thomas Henry Huxley

Thomas Henry Huxley does not appear in this article. I assume this article has been edit warred by creation science people, so I want to suggest adding content about his role in proving human evolution at talk before WP:bolding it in. PPdd (talk) 16:48, 31 January 2011 (UTC)

He does appear in History of evolutionary thought, and it seems appropriate to mention him in the history section here as well. __ Just plain Bill (talk) 18:01, 31 January 2011 (UTC)

Please don't forget that this article is already very big, to the point of it being hard to edit on some computers I use.--Andrew Lancaster (talk) 21:24, 31 January 2011 (UTC)

I put in a sentence. He plays a special role in evolution history since he is the first to prove empirically the falsity of the Bible re humans, and caused "evolution" to become a household word. I also added a sentence on Morgan (chromosomes). PPdd (talk) 22:07, 31 January 2011 (UTC)

Not against passing reference to major figures, but please everyone remember this article is already very full indeed. Much of it could be compressed though. FRIENDLY PROPOSAL: Every time someone adds something, please also do some "compression"?--Andrew Lancaster (talk) 22:11, 31 January 2011 (UTC)

I just knocked out some words, and will come back for more. I like short, easily read articles, too. PPdd (talk) 22:14, 31 January 2011 (UTC)

BTW, I think, given what Huxley is famous for, that it is interesting to point out that the first really well known claim that man might be descended from irrational apes, was perhaps Rousseau. He even thought some great apes might be humans. This was all part of his chain of reasoning concerning the Social Contract which was considered to have triggered massive cultural upheaval, such as inspiring the French Revolution, Marx, German Idealism etc, so it was not an un-influential paper. Maybe better for the history of evolutionary thought article though.--Andrew Lancaster (talk) 22:18, 31 January 2011 (UTC)

I am generally unfamiliar with Rousseau's work, so can't well comment. But I think this article is mostly about science stuff. I wouldn't object to you putting it in both, however, if it has RS. PPdd (talk) 22:43, 31 January 2011 (UTC)

I'll keep it in mind for the history article. I think it may or may not fit. It is important with respect to the history of the idea of man being related genetically to other animals.--Andrew Lancaster (talk) 21:06, 2 February 2011 (UTC)

Historical faces

History of evolutionary thought is FA. It has a fair number of illustrations. None of them are of faces. This articles chapter on the same subjec has four faces and nothing more. I suggest we replace all the faces with one of the illustrations in the "main article". Remember, we need to reduce the present stuff to make room for new stuff. --Ettrig (talk) 08:41, 2 February 2011 (UTC)

Macroevolution, eco-evo-devo, hierarchal, multi-level selection, and other aspects are missing

• The lead and other sections of this article give only small snippets of information about macroevolution and hierarchy in evolution, which are central concepts in evolutionary thinking, practice, history, and in the science of evolution in general. The article does not synthesize the information very well - it presents this as an either or case of evolution, most of it is microevolution, there are snippets of macroevolution that are not explained very well, and nothing is mentioned about evolutionary developmental changes in a context beyond the classical gene to phenotype model with minimal platitude given to environmental influence.

• Richard Lewontin (Lewontin, R., 2010, Not so natural selection, New York Review of Books, May 27.) expressed his concerns with what I see as almost a direct copy of what is in the lead of this article:

The modern skeletal formulation of evolution by natural selection consists of 
[several] principles that provide a purely mechanical basis for evolutionary change, 
stripped of its metaphorical elements:
# The principle of variation: among individuals in a population there is variation 
in form, physiology, and behavior.
# The principle of heredity: offspring resemble their parents more than they resemble 
unrelated individuals.
# The principle of differential reproduction: in a given environment, some forms are 
more likely to survive and produce more offspring than other forms...
# The principle of mutation: new heritable variation is constantly occurring.
The trouble with this outline is that ...[t]here is an immense amount of biology 
that is missing.

• If there is an immense amount of biology that is missing in that description that closely parallels the lead of this article, then I have to ask if this article is doing an adequate job of defining evolution? The answer is no. There is an IMMENSE amount of evolution that is missing in this article and although I understand that not everything can be covered, the censure of anything that steers away from gene-centered evolution is disturbing and appalling. The lead defines evolution using the skeletal population level model. However, I think Keven Padian recently and aptly described (see [11]) part of the problem that occurs when you use this approach as the sole means of describing evolution:

"The reason why we study macroevolution as a separate subject from population biology is that the things that happen at the population level do not translate very predictably to the level of the clade. They are different hierarchical levels, as Niles Eldredge, Stephen Jay Gould, and many other paleontologists have pointed out for decades (e.g., Eldredge 1985). It is not that these levels are inconsistent or incompatible. It is simply that what happens at one level does not predict or describe what will happen at the other."

• Many other publications on evolution (including textbooks on evolution[12]) have made similar statements, e.g.[13]: "Darwin’s proposal carries a more general message for contemporary discussions of macroevolution, namely that microevolution alone cannot explain macroevolution. Understanding macroevolution requires the integration of ecology, evolution and the role of history in shaping the diversification or decline of lineages." This was also summarized by Joel Cracraft in 1982[14]:"This alternative conception of macroevolution, which sees the problem of evolution as primarily a question of the origin of taxonomic discontinuities, follows logically from two premises: (1) that basic taxonomic units (call them species) can be-and are-definable as discrete units in space and time, and (2) that the origin of such units (speciation) is not merely a problem of accumulating gene or genotype change." Furthermore, "We would argue that, far from being driven by the genome, evolution is a top–down process where higher-level phenomena set the context for the operation of lower-level processes. The greater the magnitude of the higher-level phenomena, the greater the evolutionary effect. However, it is true that lower level processes can in principle penetrate to higher levels and sometimes do. For example, we recognize that evolutionary developmental biology or evo-devo is an important new field with significant implications for our understanding of evolutionary patterns and processes (e.g., Hall, 2003)."[http://www.paleo.ku.edu/geo/faculty/BSL/EvolBiol2007.pdf

• The lead mentions punctuated equilibrium, but this is only one theory among many others that have been used to examine macroevolution in biology and leaves out much that has been described about macroecology and the long-term persistence of environmental constraints that has macro-time effects on evolutionary outcomes. There is almost nothing stated about evolutionary trees and transitions - cetacean evolution, for example, "fossil record of whales and dolphins (Cetacea) has made them an exemplar of macroevolution."[15] The issues that I am raising here is more than a divide between micro and macroevolution - it is the hierarchical perspective from genes, cells, organs, to species and the ontogeny of adaptation within those biological systems that is absent from this article, yet these very perspectives are pervasive in the literature on evolution. There is also a large body of research dealing with self-similarity, complex systems theory & criticality that provides non-linear explanations as to why we would not necessarily expect a gradual continuum from micro- to macro- outcomes (e.g., [16], [17], [18], [19]), which has been experimentally demonstrated in a biological setting: "Using global gene expression data from macrophages stimulated with a variety of Toll-like receptor agonists, we found that macrophage dynamics are indeed critical, providing the most compelling evidence to date for this general principle of dynamics in biological systems." [20] I am not suggesting that we go into the complex details, what I am saying is that the definition of evolution in this article is so narrow that people cannot grasp the full-scope or understanding of what evolution is beyond the skeletal design that Lewontin outlined that matches the general description of this article.

• Multilevel selection also brings many aspects of developmental biology, group selection, and macroecology into the fold that are hardly mentioned and just given peripheral or minimal reference in this article - despite an excessive amount of literature that has been written in this area with experimental evidence to back up the theory (experimental evidence of group selection for example - [21]). Developmental systems theory, for example[22], and other advances in gene regulatory networks (e.g., [23], [24]) are changing our understanding of evolution as it is mechanically described in the lead to this article: "This micro-evo-devo synthesis promises great advances in our understanding of such things as the genetic basis of adaptation, how evolutionary change can be channeled or constrained by previously evolved developmental programs, and how population divergence leads to speciation (Wagner 2000, 2001; Porter and Johnson 2002)."[25]

• The synthesis between evolutionary and devolopmental biology is completely absent from this article (with heterochrony, homology, and ontogeny are either not mentioned or defined - despite their central role in evolution, e.g., [26], [27],[28], [29]) and despite the glaring relevance of this topic:

Genes and the inherited activation and repression states of genes are insufficient; both a component (unit, module) and a mechanism (epigenetics, emergent properties) between genes and structures are required. The fields of developmental genetics, life history theory, morphogenesis and pattern formation, phenotypic plasticity, physiological genetics, physiology, and reaction norms, all exist because neither developmental nor evolutionary change can be explained by genes alone.[30]

Adult animals are not merely large aggregates of cells. They consist of hierarchically organized structural and functional subunits. These modular parts make possible complex anatomies without excessive demand on genomic complexity ( Riedl 1978). Modules are not static in ontogeny, nor is development a single stream of events. Ontogeny is composed of a large number of dissociable processes and subunit parts and is thus fundamentally modular ( Raff 1996)....Thus, differentiation of a module can be triggered by the expression of individual switch genes. The genes involved in regulatory chains are often activated by epigenetic links between modules. These generally take the form of extracellular signaling molecules produced by the signaling cell, which interact with receptors in the responding cell that pass on a signal via protein kinases or other second messenger systems to trigger expression of a chain of genes. The result is production of transcription factors that govern the path of differentiation of the receiving cell. The profound inductive effects long recognized by embryologists represent the effects of modules on the gene expression states of neighboring modules.....With the use of the same standard parts and genes, new genes do not have to be invented each time development is altered. In the evolution of new ontogenies, standard parts are used over and over. The evolutionary outcome depends on modified expression of a relatively small number of regulatory genes and on their downstream gene targets.[31]

• Even George Williams (who inspired Dawkin's gene reductionism) has given his input that diverges from the gene-reductionist synthesis[32]: "the microevolutionary process that adequately describes evolution in a population is an utterly inadequate account of the Earth's biota...due to enormous variability in the persistence of ecological niches." (taken from Mark Ridley review article in Nature "Problems in Evolution" [33]). The ecological perspective that Williams talks about is important in an evolutionary context (see for example [34] - showing a major macro-ecological/evolutionary transition at the Ediacaran), holey adaptive landscapes [35], community level or macroecological response [36], [37], and descriptions by Douglass Futuyma on macroevolution in this context: "Conversely, community–ecological complexity affects all aspects of the macroevolution of plants and insects."[38]

• I believe that this article would benefit with a bit of clarification on the distinction between population level anagensis versus longer term cladogenesis and the different kinds of research approaches that are used, such as birth-death models in the fossil record (e.g., [39], . "Do supraspecific taxa evolve? Certainly Gould (Gould 2002; Hubbell 2005) and many others have thought so."[40]

• I will leave it at this. I have been in here numerous times over the years and have tried very hard to eek out even a tiny bit of consensus that could weave some of these broader issues into this article. However, there is fierce resistance and censure that is going on in here and it is very unfortunate. I have been ridiculed, called a liar, and encountered levels of rudeness from other editors that I've never seen in any other article (and I've contributed much and written extensively for wikipedia)! These ideas are scientific and they are pervasive in evolutionary studies. Editors in this article should be much more receptive to these ideas and happy that someone was willing to come in here and assist. I am shocked and stunned at the level of censure and resistance in this particular article and there are some editors in particular who are problematic in this regard who need to take a step back and reflect on the censure that they have promoted. Even a simple change in this article gets revoked back to the standard gene-reductionist model, so time and hard work gets wasted even if reliable sources are used. I could understand if I was coming in here and promoting intelligent design, but these ideas are about EVOLUTION. A hierarchical context is necessary to understand evolution in its full context - theoretically, historically, and experimentally. I'm retiring from evolution in wikipedia and will work in places where my feedback is much more greatly appreciated. However, I wanted to leave with this final input in the hopes that other volunteer editors who come here will not face the same degree of resistance and personal attack that I experienced despite my best intentions.Thompsma (talk) 23:37, 28 January 2011 (UTC)

Thompsma I feel your pain buddy. If you look back you will see I made comparable arguments for epigenetics (although you note I still am trying be patient too and hold my reservations because I am so biased to agree with Jablonka and Lamb), and why the heck multilevel selection isn't recognized in balance is wrong. You have made some brilliant arguments with well sourced references. Microevolution and a simple Dobzhansky shift in gene alleles can't explain macroevolution (nor the large duplication and inversion events-the article on the amphiouxus genome and relation to tunicates and chordates you can see the kind of changes that have taken place)and a heirachial or multilevel process is just about empirically obvious-the written language is a heritable factor of evolution and passing on information as much as bird song. My only complaint is your style appears to irritate but I believe that is the frailty of the written language-I guarantee you in person we would be jovial and have a rather wonderful conversation and debate. As I said above- the quicksand of our intellect-I've been banned from one blog for falling into similar a situation in arguing over aging and intellect (yeah we fall apart pretty quick but most nobel laureates are in their 40's with their seminal work -don't get me started with the little age discriminator moron I was arguing with). I know everyone thought I was pscyhotic LOL. Also we make tonque and cheek comments that really fall by written word. Take a break and return, I believe you've planted a seed and other editors will pick up your torch. I hate to see good editors leave so I hope you will return my friend and realize your efforts weren't in vain (I apologize if I've given you some $hit). Regards GetAgrippa (talk) 01:39, 29 January 2011 (UTC)

I'm offering an olive branch. Should you decide to come back and would like to work with me on revamping this article one section at a time, let me know. I have been and still am interested in incorporating multilevel selection, macroevolution, evolution and development, and evolution of genes and genomes. Your knowledge base would be immensely helpful. But my priority right now is condensing this article first before expanding it to include these major topics. Minus the silly back and forth between us, quite a bit was accomplished within such a short period when there was collaboration. Imagine the long term. mezzaninelounge (talk) 04:33, 29 January 2011 (UTC)

Yes, this article would benefit from more good material on macroevolution. The need is even more desperate in the macroevolution article. Adding macroevolutionary stuff there would be completely uncontroversial. With a good text there it would be easier to illustrate what should be here. But this article is already too long, so Daniels effort to abbreviate it should also be supported. A minor comment: The lead is supposed to be an excerpt of the rest of the article. So we cannot start by adding new macroevolutionary stuff in the lead. Could we sort the macroevolutionary stuff into one chapter called microevolution or population genetics, to show that this part does not try to describe all of evolution: MICROEVOLUTION: Population genetics; Mutation; Sex and recombination; Gene flow; Natural selection; Genetic drift. --Ettrig (talk) 21:18, 29 January 2011 (UTC)

Great idea Ettig. Perhaps have a section between 5.4 Speciation and 5.5 Extinction in Outcomes of Evolution called "Microevolution and Macroevolution". So it would fall under outcomes as

5.4 Speciation, 5.5 Microevolution and Macroevolution, and then 5.6 Extinction. It would serve us well to address evoluton through space and time. We could discuss the differences between the two and address genetic differences too. Microevolution-shifts in gene alleles like in three spine sticklebacks vs. Macroevoluton and large genomic duplication events,inversions, etc. and changes above the level of species. There is a rich source of genetic articles in comparative genomics. It is easy to "see" microevolution as an outcome but macroevolution and explaining the history and diversity of life is a greater challenge. Comparative anatomy offers a glimpse into evolution so why ignore comparative genetics and molecular evolutoin. We offer only half the argument. I'm not suggesting an opus just somewhere in the article where we address the issue or link to main article-I see it as a pretty major omission. Good Golly Thompsma has done all the homework and offered a rich resource of references. GetAgrippa (talk) 22:25, 29 January 2011 (UTC)

With all due respect, may I suggest that you guys try collaboraing first on making the Macroevolution article a great article, and then the Evo-Devo article a great article (or vice versa) first? Two reasons: first, it would make for an easier collaboration. Second, after making those great articles it will be easier to decide how to summarize them here. Slrubenstein | Talk 19:51, 30 January 2011 (UTC)

First I would like to say thank you to those of you who have offered the olive branch, but I have decided that I will still be leaving evolution and will work in other articles. I thought I would return to suggest a few final things in response to the posts that this received. I like Slrubenstein's idea to expand on the other articles - and this is probably where I will go. I also want to clarify that my post was not just about macroevolution, but the hierarchical context of evolution (genes, populations of cells, organs, organisms, populations, species, and higher taxa) that needs to be threaded into the overall idea. If sections are to be added/amalgamated in this vein I would suggest sections on: 1) Phylogenetics and evolutionary trees with special emphasis on homology explaining DNA and morphological character states, 2) Evolution and developmental biology with possible emphasis on ecology (i.e., evo-eco-devo), 3) Microevolution and Macroevolution. If done properly, this information could be added in such a way to reduce the size of the article.Thompsma (talk) 18:12, 1 February 2011 (UTC)

Off you go then. I will just wait till everyone is ready to expand this article. Right now, I just don't have the time to commit to write new section pieces for this article, let alone any other article. I will continue to identify areas that need condensing and will help out with the editing process when this article gets expanded again. I think I will be able to make positive contributions through editing rather than writing new sections. Cheers. mezzaninelounge (talk) 00:46, 2 February 2011 (UTC)

Perhaps like directing students for major field papers or dissertations, we should start with an outline. Then work out the nitty gritty in sections. I've noted many of the subarticles have drifted a bit and there needs to be consistency. I too am busy with a full load of teaching, trying to get some preliminary data to write a grant, and wondering if I can keep up because it seems I'm physically falling apart (can't see crap, hear crap, and my 8am lectures sound like some Gregorian chant- a lot of "ummmmM the aorta ummMMM is the site of uuMMMMM" Sheez ). GetAgrippa (talk) 02:32, 2 February 2011 (UTC)

Teaching at 8 am huh? I can relate. What do you teach? mezzaninelounge (talk) 19:03, 2 February 2011 (UTC)

Yep I'm not a morning person. At 8am it is Anatomy and Physiology (which I love). I've tried getting up earlier but my brain just don't start kickin till about 9. I remembered you mentioned neuro as your field are you teaching neuro?GetAgrippa (talk) 02:05, 3 February 2011 (UTC)

No I don't teach Neuro (would love to). Just an introductory biology course for non-majors. Easy. :D mezzaninelounge (talk) 16:30, 3 February 2011 (UTC)

People interested in this thread should read the following article [41] and the posted comments that follow. There is a problem with the model of evolution as it is portrayed in the lead, because it does not explain evolutionary stasis over long-time periods. This is why Rupert Riedl's evolutionary burden concept ([42], [43]) and other evo-devo biologists have resorted to other means to explain these phenomena that cannot be explained by the skeletal formulation in the lead, which is also why Lewontin stated that it is missing an immense amount of biology as we see it in the real world. The model in the lead cannot explain stasis or the mechanisms of character origination (see [44], [45]). People are going to question evolutionary theory in the way that it is inadequately explained in this article. If evolution is just a bunch of traits with matching genes that change in populations and proportions over time, then how can you explain the evolutionary stasis of an insect body plan for over 100 million years? Was it pure chance that the same traits kept surviving generation after generation, population after population? Of course there are adaptations that help to explain the stasis of these traits, but for 100 million years? Is it really possible that this evolutionary stasis survived battery of "the change over time in the proportion of individual organisms differing in one or more inherited traits" for so long? It is also unlikely and improbable that "the major sources of such variation are mutation, genetic recombination and gene flow." - I don't believe it, Stephen J. Gould didn't think so, and neither do many of the authors in the articles I cite above think that this is the situation. It does not make logical sense. Certainly, genetic mutation is a source of variation, but other mechanisms that are directly accountable to the physical world - such as cellular morphogenic fields - are more potent sources of observable variation that survive and responsible for character origination that works, because evolution is burdened (sensu Riedl).Thompsma (talk) 20:59, 4 February 2011 (UTC)

How can this be explained? This paper[46] (Eldredge, N., Thompson, J. N., Brakefield, P. M., Gavrilets, S., Jablonski, D., Jackson, J. B. C., Lenski, R. E., et al. (2005). The dynamics of evolutionary stasis. Paleobiology, 31(2_Suppl), 133-145.) concludes:

Both theoretical and empirical studies of the past decade suggest that the complex pattern of selection imposed on geographically structured populations by heterogeneous environments and coevolution can paradoxically maintain stasis at the species level over long periods of time. By contrast, neither lack of genetic variation nor genetic and developmental constraint is probably sufficient in and of itself to account for species-wide stasis.

This paper[47] (Pagel, M., Venditti, C., & Meade, A. (2006). Large Punctuational Contribution of Speciation to Evolutionary Divergence at the Molecular Level. Science, 314(5796), 119-121.) concludes:

Punctuational episodes of evolution may play a larger role in promoting evolutionary divergence than has previously been appreciated...Whatever the mechanisms of the effects we have characterized, relatively rapid and punctuational bursts of evolution driven by speciation appear to make a substantial contribution to molecular divergence. By comparison, we found no molecular counterpart to the periods of stasis noted for morphological traits (1, 3, 4, 35, 36), the other half of the conventional punctuated-equilibrium description of morphological evolution. There need not be any conflict between these two observations as it is well known that molecular change can occur independently of morphology.

Thompsma (talk) 23:55, 7 February 2011 (UTC)

Basic adaptation?

The article says: Adaptation is one of the basic phenomena of biology ... Adaptations are produced by natural selection. I find this contradictory, or at least confusing. Of these two, only selection is basic. --Ettrig (talk) 12:19, 4 February 2011 (UTC)

Gene flow in lions?

The illustration to paragraph genetic flow says that there is genetic flow between prides of lions. I hold this to be true. But isn't it a rather misleading illustration to this paragraph. The main context here is populations that evolve. Prides are very small groups and the referenced article says that mating partners are usually unrelated. This means that gene flow is so massive that the pride can hardly be seen as a population. --Ettrig (talk) 13:42, 5 February 2011 (UTC)

It sounds to me like there could indeed be a better choice of illustrative example. Can anyone think of a better and clearer one?--Andrew Lancaster (talk) 15:15, 5 February 2011 (UTC)

Why not mention gene flow from transgenic species to wild type of fish or hatchery raised salmon and wild type gene flow, or from trangenic plants to other populations like Roundup resistance jumping to other species. They are more novel examples but demonstrate how promiscuous DNA can be and "flow". GetAgrippa (talk) 03:27, 9 February 2011 (UTC)

Given that this is a kind heading article connecting to more specialized articles perhaps we should keep Mr/Ms Average in mind in selecting examples.

• Animal examples, as opposed to plants or microbes, are good for showing a basic concept rather than the complications?
• Maybe to help the imagination, it is good to choose an example with real geographical barriers, like for example movements between the two Americas, or over mountain ranges.

What about North American wolves?--Andrew Lancaster (talk) 11:03, 9 February 2011 (UTC)

Yes, what about North American wolves? Maybe I should just draw some circles and arrows. Corvus corone and Corvus cornix have stable distributions. Because of the wide hybridization area in continental Europe, there must be considerable flow. Have no ref on the flows though. --Ettrig (talk) 11:26, 9 February 2011 (UTC)

Social Darwinism

The article now ends: It was later expanded by others into ideas about "survival of the fittest" in commerce and human societies as a whole, and led to claims that social inequality, sexism, racism and imperialism were justified.[288] However, these ideas contradict Darwin's own views, and contemporary scientists and philosophers consider these ideas to be neither mandated by evolutionary theory nor supported by data.[289][290][291] I think we do not need to spend so much effort stating that this view is unfounded. May I change to
It was later expanded into ideas about "survival of the fittest" in commerce and human societies as a whole, and led to incorrect support for claims that social inequality, sexism, racism and imperialism were justified.[288]
It would be good to get rid of the three references. As in all cases, I will of course ensure that this is covered in a subtopic article. --Ettrig (talk) 11:42, 11 February 2011 (UTC)

Tempting, but neutrality is an important aim, so I suggest saying "controversial" instead of just "incorrect".--Andrew Lancaster (talk) 21:11, 11 February 2011 (UTC)

OK with me. Would unfounded be closer to neither mandated by evolutionary theory nor supported by data? My aim is to abbreviate, not to change the meaning. --Ettrig (talk) 21:29, 11 February 2011 (UTC)

I think that it was Spencer who coined the term "survival of the fittest," and I don't see a problem with saying the view is incorrect; we could use the word "unfounded" but the point is that it is incorrect to attribute these views to Darwin, and it is incorrect to suppose that evolutionary biologists strive to justify social arrangements. Science can explain, but not justify. Slrubenstein | Talk 22:05, 11 February 2011 (UTC)

Well, I understand your point but on the other hand there are people who still argue the other position and get published? People for example point, IIRC, to Darwin approvingly calling Spencer "our philosopher"? Didn't Huxley also make something of a similarity between Spencerism and Darwinism? The two streams of thought are separate, no doubt. I believe Spencer himself always pointed out that his philosophy had already been published before Darwin's theory came out. But there were at least some links in 19th century thinking. I think it is a similar problem to the one we face handling teleological understandings of Darwin, where evolution has a direction. Because also in that case, as individuals who know the subject somewhat we want to argue it is wrong, but biologists have sometimes written this way. I'm not going to take a strong position at this stage, but I do suggest keeping neutrality in mind at all times, not just for "idealistic reasons" but also because neutrality tends to result in more stable texts.--Andrew Lancaster (talk) 08:23, 12 February 2011 (UTC)

I think the Social Darwinism blurb is in need of a rewrite. Amongst other things: "Another example associated with evolutionary theory that is now widely regarded as unwarranted is "Social Darwinism" — It's not clear what this is an example of, nor is it clear why this is "another" example since the rest of the section is pretty free of anything you could consider to be a sequence of related examples. I'm also unsure how an example could be warranted/unwarranted in the sense it seems to imply. Also, saying that an idea is "misused" when used to justify something — no matter how abhorrent one might find that particular something — implies that there is a correct use for those ideas and is decidedly non-neutral. 174.102.196.179 (talk) 20:57, 20 February 2011 (UTC)

Notability in lead

MOS:LEAD requires tht the lead should explain why the subject is interesting or notable. I don't think this article fulfills this requirement. Evolution has created wondrous life forms (all the life forms), for example the exuberant peacock's tail, the eye that can register the colours and forms in that tail, the language that can handle this abstract relation and my intelligence that can make this observation. Evolution also create photosynthesis that molecule by molecule converted the carbon dioxide in the atmosphere to oxygen and the principal ingredient in the life forms. Darwin understood this need to convey the magnificence of evolution and how this emanates from general laws of nature. He wrote towards the end of Origin of Species: --Ettrig (talk) 12:51, 19 February 2011 (UTC)

It is interesting to contemplate a tangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent upon each other in so complex a manner, have all been produced by laws acting around us. These laws, taken in the largest sense, being Growth with reproduction; Inheritance which is almost implied by reproduction; Variability from the indirect and direct action of the conditions of life, and from use and disuse; a Ratio of Increase so high as to lead to a Struggle for Life, and as a consequence to Natural Selection, entailing Divergence of Character and the Extinction of less improved forms. Thus, from the war of nature, from famine and death, the most exalted object which we are capable of conceiving, namely, the production of the higher animals, directly follows. There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone circling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.

A bit long to fit into the intro? What's wrong with something like your own words above like "Evolution is the cause of the diversity of all life on earth"?

Thanks for the formating. I would like to expand the formulation a bit to hint at the magnificent character of the currently existing result. Evolution is the process that has produced all the diversity and intricate mechanisms in the living organisms. We will surely have a debate that improves this formulation considerably. There is at least one aditional problem. The lead is not to contain any facts that are not in the main part of the article. I think that in the history of life on earth (or somewhere else) we should add some of the more remarkable results of evolution. --Ettrig (talk) 15:14, 19 February 2011 (UTC)

Direction is ok but indeed not yet quite right. "Intricate mechanisms"?--Andrew Lancaster (talk) 18:33, 19 February 2011 (UTC)

Well, as long as we avoid that Pentateuchal term ;-) . . dave souza, talk 18:49, 19 February 2011 (UTC)

Evolution is the process that has produced all the diversity of living organisms. Charles Darwin, the portal figure in early study of evolution characterized the result as endless forms most beautiful and most wonderful. --Ettrig (talk) 19:09, 19 February 2011 (UTC)

Personally I think OK, except I'd choose another word than portal.--Andrew Lancaster (talk) 09:43, 20 February 2011 (UTC)

Recent example of evolution

I'm not familiar enough with this article to know whether this information is worth including (here or in a daughter article), so instead of being bold, I'll just mention it here and let others decide. It's a recent example of evolution in which the specific mutation involved has been identified. This is what I added to the Microgadus tomcod article:

After General Electric dumped polychlorinated biphenyls (PCBs) in the Hudson River from 1947 through 1976, tomcod living in the river were found to have evolved an increased resistance to the compound's toxic effects. Scientists identified the genetic mutation that conferred the resistance, and found that the mutated form was present in 99 per cent of the tomcods in the river, compared to fewer than 10 percent of the tomcods from other waters.

JamesMLane t c 19:44, 19 February 2011 (UTC)

This would probably belong over at Evidence of common descent as an example of natural selection. A. Z. Colvin • Talk 00:51, 20 February 2011 (UTC)

I looked at the list of daughter articles and that possibility occurred to me. This item, however, while it's evidence of natural selection, is not evidence (at least not very direct evidence) of common descent. The creationists who deny evolution would certainly say that tomcods have never been anything but tomcods, regardless of their vulnerability to PCBs. Because that article includes examples of adaptation through natural selection, perhaps the article should be renamed to reflect its broader scope. Anyway, I'll add the tomcods there for lack of a better alternative. JamesMLane t c 23:02, 21 February 2011 (UTC)

Thank you for adding it there. I agree with you that it is not “common descent” but for the time being, examples of natural selection are included. I personally think the article needs to be renamed back to its old title Evidence of Evolution or something similar being that the article consists of a large amount of examples spanning many different fields of biology. It could also be split up into more than one article if it warrants. It’s a work in progress. A. Z. Colvin • Talk 23:26, 21 February 2011 (UTC)

Evolution only relates to "inter-breeding populations"?

This doesn't sound right. This by definition excludes the possibility that asexual creatures could evolve. Jcurious (talk) 22:46, 2 March 2011 (UTC)

Agree. mezzaninelounge (talk) 23:55, 2 March 2011 (UTC)

My bad. However this is a reminder that in a way what we mean by evolution is different for organisms which reproduce asexually. So a problem remains. If you remove reference to populations you potentially make the definition wrong for animals and plants, because for them we do not normally say evolution is happening when one individual only has a novel mutation?--Andrew Lancaster (talk) 09:46, 3 March 2011 (UTC)

The mutation is for evolution like the atom for chemistry. An iron atom is not a piece of iron. But it is difficult to say how many atoms are needed to make up real metal. When a mutation appears, the frequency for the created allele increases. How much must the frequency change to be counted as real evolution? Evolution is plagued by fuzzy concepts: population, species, gene, trait ... In this article we should try to explain to a rather detailed level how populations evolve and also mention very briefly that the details are different for asexual organisms. --Ettrig (talk) 11:37, 3 March 2011 (UTC)

OK, but the lead definition needs to be compact and needs to cover the options somehow.--Andrew Lancaster (talk) 11:43, 3 March 2011 (UTC)

Most asexual organisms still display horizontal gene transfer(gene flow). But even Bdelloid rotifers escape Muller's ratchet by gene duplications, which then mutations can alter to new functions. Duplication events seem inevitable no matter the life form-as monozygotic twins even have differences in gene copy number. So Dobzhansky's definition of shifts in gene allele through successive generations would only apply to sexual organims. I guess just a "genetic change" is about as neutral as you can get. The genetic change can of course precede the trait-like drosophila and resistance to pesticides is from a 35,000 year old transposon that finally jumped to generate the trait of surviving the pesticide in the last 200 years. I guess it begs the question when did drosophila "evolve" when they acquired the transposon or when it developed a function? GetAgrippa (talk) 18:25, 3 March 2011 (UTC)

Definition of evolution

131.251.142.18 (talk) 12:58, 24 February 2011 (UTC)One of the strengths of Wikipedia is that it can offer up to date definitions of items, incorporating new information and insights quickly. However,one of its weaknesses is that any definition is only as good as its last edit, and the definition of evolution, seems particularly prone to poor, sometimes erroneous explanation. The first line of the current definition illustrates this:

"Evolution (also known as biological or organic evolution) is the change over time in the proportion of individual organisms differing in one or more inherited traits.[1] Inherited traits are particular distinguishing characteristics, including anatomical, biochemical or behavioural characteristics, that result from gene–environment interactions."

This is not even close to being right. Evolutionary history is not about changing proportions of organisms, any more than chemistry is about the changing colours of solutions. A definition of evolution must incorporate variation, heredity and natural selection, to explain speciation and adaptation (descent with modification). Evolution as an observed phenomenon is well understood and fairly straightforward to define; it should not be the subject of constant discussion and interpretation, particularly if it results in erroneous definitions such as the current entry. The reference given for this definition is Futuyma’s excellent book “Evolution” 2005. However in my copy (2005) of this book the definition is as follows:

"Biological evolution is change in the properties of over the course of generations. The ontogeny of an individual is not considered evolution; individual organisms do not evolve. Groups of organisms which we may call populations undergo descent with modification. Populations may become subdivided, so that several populations are derived from a common ancestral population. If different changes transpire in the several populations the populations diverge.”

I have suggested previously that the Wikipedia entry should be based on a standard text book definition of evolution such as this one, and expand from that. Perhaps the moderator(s) for this topic could address this long standing problem.

EMT (Cardiff) 131.251.142.18 (talk) 12:58, 24 February 2011 (UTC)

Actually this opening line has been discussed a lot just recently, and at least some of the concerns you raise were also discussed at that time. I think there were other concerns also, which you maybe have not considered, and of course we have to try to cover all concerns. Anyway, it was not put together randomly. Just a suggestion but if you have time can you please first look over this talk page' recent history and see if that explains the sentence for you? Concerning the word proportions I did not insert it, but keep in mind that species are made up of populations, and do not have one single set of characteristics but rather a set of many possible variants. Furthermore, when speciation occurs this set of characteristics changes in proportions, but not necessarily any other way? --Andrew Lancaster (talk) 13:14, 24 February 2011 (UTC)

My point about changing colours in chemistry was to address just that point. The changing proportions of various characteristics from one generation to the next does not constitute a definition of evolution, any more than the changing colours of chemical reactions defines chemistry. Note that the proportions of the same population characteristics (e.g. height, weight, size, distribution etc) change from day to day but this is not evolution.

The main issue is that, not only is the current definition a misquote of the Futuyma defintion which it cites, but it is just plain wrong, and whilst there are many interesting and exciting discussion points in Evolution, the definiton of the term should not be one of them.

EMT(Cardiff)131.251.142.18 (talk) 13:31, 24 February 2011 (UTC)

One author's formulation, that we may take inspiration from: All the changes that have transformed life on earth from its earliest beginnings to the diversity that characterizes it today. Neill Campbell, Biology, Glossary, 1996.

Another one: ...Organic evolution, or biological evolution, is a change over time of the proportions of individual organisms differing genetically in one or more traits. Such changes transpire by the origin and subsequent alteration of the frequencies of genotypes from generation to generation within populations, by the alterations of the proportions of genetically differentiated populations of a species, or by changes in the numbers of species with different characteristics, thereby altering the frequency of one or more traits within a higher taxon. Douglas Futuyma, Evolutionary Biology, Glossary, 1998.

Yet another one: Genetic changes in populations of organisms through time that lead todifferences among them. Monroe Strickberger, Evolution, Glossary, 2000.

--Ettrig (talk) 21:18, 25 February 2011 (UTC)

Would other agree that a change in the proportion between black and white forms of the peppered moth are described as evolution? Does evolution require speciation? I think not. If it does not require speciation, then what would evolution which is not quite speciation look like if not a change in proportions of characteristics in populations?--Andrew Lancaster (talk) 22:22, 25 February 2011 (UTC)

This thread starts with the claim that the start of the article is not in accordance with Futuyma. Comparing with Futuyma's glossary definition, quoted above, I find that the opposite problem is at hand. It is a case of plagiarizm. --Ettrig (talk) 07:58, 26 February 2011 (UTC)

Well the wording is different, so putting in quotes would not be right, but it certainly needs to cite the source.--Andrew Lancaster (talk) 10:31, 26 February 2011 (UTC)

The latest change has the effect to say that evolution is only about proportions within populations. This limitation is not correct and not according to the Futuyma quote above, which adds alterations of the proportions of genetically differentiated populations of a species, or by changes in the numbers of species with different characteristics. When individuals die or are born, this changes the proportions within populations. But changes on higher levels also contribute to evolution: when populations and species fork and go extinct. --Ettrig (talk) 13:35, 26 February 2011 (UTC)

Logically speaking both these options seem to me to be covered by the new wording, but I'm open to new ideas. On the other hand I also have doubts that an extinction is a case of evolution.--Andrew Lancaster (talk) 15:27, 26 February 2011 (UTC)

When sentence 3 is taken into account, the text certainly limits evolution to occuring within populations. This is not in accordance with the Futuyma quote above. Your personal doubts have of course very little weight in this discussion, as hahave my personal beliefs. I ask you to see that Futuyma in the quote above uses a very clumsy and elaborate formulation above to make sure that it is understood that evolution can occur above the population level. One extinction is probably not evolution. But individual death and reproduction have both selective and stochastic (drift) causes, so have extinction, speciation and population bifurcation. --Ettrig (talk) 16:51, 26 February 2011 (UTC)

• First of all we obviously do not want to have an elaborate and clumsy sentence. But let's assume we can get the same meaning in a neater way.
• Concerning what the first sentence should say, to address the remark you make: Of course my own opinion could be enough, iff we would have a clear consensus that my opinion is just a summary of mainstream consensus. Was my remark a controversial one compared to the mainstream? I phrased it such a way that I was thinking it might actually be a common opinion.
• If that is not the case, then no problem. But anyway, we do not of course have to limit ourselves to one source. We will find many definitions and they all differ. If we select just one of them as the basis of our opening lines then in fact we are supposed to be quite careful about doing this. If, as I was suggesting, it contains a rather unusual aspect, we should consider whether that is appropriate, especially in the first sentence. For example if it is just a bit unusual, maybe we can keep this point, but discuss it a little later.--Andrew Lancaster (talk) 17:13, 26 February 2011 (UTC)

As part of the definition, shouldn't we distinguish between macroevolution and microevolution?-- Joshuajohnson555 (talk) 04:43, 10 March 2011 (UTC)

No, because they are considered to be exactly the same thing. A. Z. Colvin • Talk 05:49, 10 March 2011 (UTC)

Macroevolution is just lots of microevolution is just a little evolution. There's no reason to include either term in the definition. -- Consumed Crustacean (talk) 06:07, 10 March 2011 (UTC)

• "The term "macroevolution" frequently arises within the context of the evolution/creation debate..."
• "The term 'microevolution' has recently become popular in the anti-evolution movement, in particular among young Earth creationists..."

In other words, this is not an appropriate place for such spurious "distinctions without difference." See Creation–evolution controversy and Objections to evolution. __ Just plain Bill (talk) 17:23, 10 March 2011 (UTC)

From what I know, macroevolution refers to speciation, which is what most people think of when they say Evolution, i.e., Darwinian evolution, while microevolution is evolution within a given species, e.g., wolves adapting to eat and digest crabs, but they're still wolves. Joshuajohnson555 (talk) 01:13, 12 March 2011 (UTC)

Only creationists have invented the difference between "macro" and "micro" evolution. It doesn't exist in real science. If you want to push a creationist POV, I suggestion creationism. Of course, if you don't have a reliable source, even there you'd be laughed out of the place. LeftCoastMan (talk) 03:50, 12 March 2011 (UTC)

Lets not bite. :) A. Z. Colvin • Talk 06:39, 12 March 2011 (UTC)

In reality, speciation occurs as small changes accumulate until members are suitably different for us to call them different "species". This is often a totally arbitrary distinction; in some cases, it's based on separate species not being able to or not choosing to interbreed (although even this criteria is confused by, e.g., ring species), and in other cases it's just because we say so (especially, but not only, in asexual organisms). So the distinction between those two terms in the context you've described is totally arbitrary, and not actually rooted in anything natural. -- Consumed Crustacean (talk) 21:45, 13 March 2011 (UTC)

new section called "background"

Given the length of this article is the new section called Background really justified? It does not in fact appear to mention evolution in any direct way.--Andrew Lancaster (talk) 06:52, 2 March 2011 (UTC)

The following Heredity section begins: Evolution in organisms occurs through changes in heritable traits – particular characteristics of an organism. In humans, for example, eye colour is an inherited characteristic and an individual might inherit the "brown-eye trait" from one of their parents. Inherited traits are controlled by genes and the complete set of genes within an organism's genome is called its genotype. This is also a trial at providing background concepts needed to understand evolution. I think the new section provides much better understanding of the material that evolution works on. My hope is that the necessary slimming can be achieved by removing less needed introductory text on heredity and variation. --Ettrig (talk) 09:48, 2 March 2011 (UTC)

I am not concerned about the section's quality, but the overall article remains very big, and we seem to have side discussions about so many things.--Andrew Lancaster (talk) 12:58, 2 March 2011 (UTC)

Agree. The new background section is overkill. I don't think it is necessary. Its presence in the article should be reconsidered. More effort should be expanded on sections directly related to evolution, e.g., macroevolution, multilevel selection, evo-devo, etc. mezzaninelounge (talk) 13:38, 2 March 2011 (UTC)

Previously the article had a lot about heritable traits. Please remove that instead of the proteins. "Heritable traits" is hocus pocus/magic, while proteins and functional RNA is explanation. Early evolutionists had severe problems of understanding because they didn't know about DNA, forget about using DNA as template for proteins. Now when we do understand some of that, evolution follows almost as a necessity. Of course replication is not always correct. Of course that can make the protein slightly different. Of course that means that the organism functions slightly differently. Since DNA is made up of the same nucleotides in all organisms and DNA defines almost everything that we are it is obvious that by successive sequence changes, one form can transmute into another. The difference I'm trying to introduce is not inclusion of background material, it is already there. We can make the task of explaining evolution much simpler if we replace heritable traits and variation of forms with proteins and DNA. We have an enormous advantage compared to Darwin, let's take advantage of this opportunity. --Ettrig (talk) 14:34, 2 March 2011 (UTC)

Ettrig, I think you are misunderstood what Andrew and I are getting at. It is not a question of whether genes and proteins are important. They are. The question is the amount of space devoted to this material, which is considerable. Such information are already covered in other articles, DNA, proteins, central dogma of biology, etc. They need not be repeated here, especially in 4 paragraphs of detail. Finally, it is a little premature to be inserting such large information into this article without first seeking consensus from the other editors. Again, I'm asking you to take a step back and look at the big picture. We're talking about priorities here. Which is more important to an article on evolution? A section on multilevel selection (as an example) or a section on gene regulation and mitosis? mezzaninelounge (talk) 15:29, 2 March 2011 (UTC)

I tried to add a more modern background description (I didn't write it myself, obviously, but pinched here and there) to replace old style background material. My aim was to remove most of what now is in Heredity. So to me the issue is to have background based on old views of heredity or background based on modern understanding of how DNA is used as a template. As a compromise, I suggest we remove the new background and also most of what is in Heredity. Multi-level selection would be very interesting. I have the book "Genes in Conflict". --Ettrig (talk) 15:33, 2 March 2011 (UTC)

Ettrig, I too support modernizing the article whenever possible. My only concern is space and devotion to certain topics. Perhaps you could list the areas (paragraphs, sentences) that you think are outdated and needs to be replaced or deleted? Please be careful. I understand you might think that terms such as traits, heredity, etc might be vague or dated, but they are still widely used in the literature [e.g., [48][49]). As a suggestion, I also recommend leaving the lead as it is for now. That part is too contentious. mezzaninelounge (talk) 15:43, 2 March 2011 (UTC)

You can't reduce heritable trait to DNA-RNA-Protein. Some song birds have genetically determined songs, but most learn their songs. This trait is passed on. Human knowledge is passed on like any trait and has influenced our evolution. Further most traits are an emergent property of genes and gene networks interacting with the environment. So really the hocus pocus becomes how does a gene mutation in calmodulin explain the differences in traits of Darwin's finches rather than bone morphogenetic protein or some neural crest homeobox mutation. GetAgrippa (talk) 13:20, 3 March 2011 (UTC)

It seems to me that there is no strong consensus for there to be the "background section" in this article. I will remove it from the text for the time being until a consensus is reached. I will also fix the lead definition. As one editor correctly pointed out, it excludes bacteria and viruses. mezzaninelounge (talk) 14:31, 3 March 2011 (UTC)

It also seems at times to be written from the perspective of a proteonomics evangelist ... "With the exception of certain types of RNA, most other biological molecules are relatively inert elements upon which proteins act. Proteins make up half the dry weight of an Escherichia coli cell, whereas other macromolecules such as DNA and RNA make up only 3% and 20%, respectively". Readers might mistakenly draw from this that proteins are the be-all-and-end-all of biology. That's true if you're an infectious prion agent passing on your spatial configuration to an untransformed protein, but the rest of us might view this as putting the cart before the horse. --PLUMBAGO 15:30, 3 March 2011 (UTC)

That passage is from Protein#Cellular_functions, a good article. I think it gives a very good description of the actual situation. I would be very interested in getting a glimpse of the alternative description. --Ettrig (talk) 15:46, 3 March 2011 (UTC)

DNA, a featured article, says in transcription, when a cell uses the information in a gene, the DNA sequence is copied into a complementary RNA sequence through the attraction between the DNA and the correct RNA nucleotides. Usually, this RNA copy is then used to make a matching protein sequence. --Ettrig (talk) 16:19, 3 March 2011 (UTC)

My point was really that, for an article on evolution, and not proteins, this text was inappropriate (≠ wrong) and liable to cause confusion. I certainly wouldn't disagree that the bulk of what passes for life on Earth is built of protein, or that there are interesting things going on with this, but just that evolution is more concerned with heritable information. Therefore, an article on evolution should tread carefully to ensure that it doesn't present material that my be misconstrued by a non-technical audience. Anyway, this is all academic as the section has been removed. --PLUMBAGO 09:54, 4 March 2011 (UTC)

This is a side issue, but if this section is going to stay can I also ask whether it has the right title? Also, unfortunately if it is going to stay I guess it might need to get longer. Right no it does not explain its own link to evolution unless you already know about the subject. (I am still not really sure we have place for it, as I explained at the beginning.)--Andrew Lancaster (talk) 17:32, 3 March 2011 (UTC)

[Evolution] has produced all the diversity of living organisms.

My issue is with the word 'all'. What evidence is there that this is the case? Is it not possible that abiogenesis created several different chains of DNA throughout the early stages of life and that this produced some (albeit a small amount) of lifes diversity? This statement seems to imply that scientists know for sure that only a single abiogenesis event ever occurred. Puppetx (talk) 20:26, 10 March 2011 (UTC)

Abiogenesis for starters, is not the same as evolution. There is a possibility that there have been more than one origins of life on earth, but all organisms that have been observed so far fit with the idea of common ancestry from a single ancestor. Even if scientists discovered two lines of organisms that came from a different origin, the phrase “evolution has produced all the diversity of living organisms” still applies. Evolution, in theory, could apply across any form of life whether it is the known life here on Earth or alien life on Mars. Evolution still produces diversity. This statement doesn’t imply that scientists know for sure that only a single origin occurred because it doesn’t talk about abiogenesis, it is talking about the diversity of life being caused by evolution. This is a fact. A. Z. Colvin • Talk 06:35, 11 March 2011 (UTC)

Yes, yes. He's well aware of what the sentence is supposed to say. What he's saying is that, taken literally, the sentence implies that no process besides evolution ever created any diversity in life. (if all A is B, it follows that no A is not B.) and we don't know that to be true. for instance, abiogenesis is a process that is not evolution and could've been responsible for diversity in life. an A that is not B. Thus the sentence, as worded, is false. Kevin Baas^talk 13:51, 11 March 2011 (UTC)

When you go back to the root of the tree of life, you find a reticulated network that connects everything. Based on much more than just DNA-sequences, there is no reason to even doubt that there might be something else than evolution playing a role in the diversity on earth. Adding qualifyers is therefore not appropriate.-- Kim van der Linde ^{at venus} 00:03, 12 March 2011 (UTC)

This passage was introduced to provide some indication of the significance of the subject. We cannot assume that the reader understands that changes in gene frequences has all these life forms as effect. Please suggest another formulation that indicates the width and depth of effects of evolution. Would it be sufficient to replace all with the vast majority of? Can anyone think of something better? --Ettrig (talk) 14:00, 11 March 2011 (UTC)

The vast majority would be a falsehood as far as we know. -- Kim van der Linde ^{at venus} 00:03, 12 March 2011 (UTC)

Okay, just brainstorming here (without looking at the context), to get things going. Here's a radically different approach:

Though evolution does not examine the origins of life on earth (that is the subject of abiogenesis), it suffices to explain how, overtime, it has come to be so diverse.

This is, at least, a perfectly true and unambiguous statement, that leaves no room for error of understanding. Notice, also, that it lists evolution as a sufficient condition for the diversity, but makes no claim as to whether it is a necessary one. This further underlines that there may be other sources for diversity, without explicitly claiming that there are. Also it is written in a more active voice, which is preferable in writing. Kevin Baas^talk 15:25, 11 March 2011 (UTC)

Kevin Is absolutely on the right track in understanding what I'm trying to communicate. If we simply dropped the 'all' would it still be implied? I like Kevin's proposal but it does seem unnecessary to include what evolution is not (abiogenesis), in the definition of what evolution is. Is it not sufficient to say?:

[evolution] has produced the diversity of known living organisms.

We are then at least qualifying it with the body of scientific knowledge. Puppetx (talk) 23:37, 11 March 2011 (UTC)

No, evolution has also produced the diversity of extinct organisms. But more important, there is nothing that even suggests that processes other than evolution has produced diversity. It is therefore not appropriate to try to qualify that. As soon as you have a self-replicating organism, whatever primitive, natural selection, genetic drift and founder effects start playing a role. As the root of the tree is pretty much a reticulated network, there is no evidence for anything besides evolution that might explain the diversity of life at this globe. -- Kim van der Linde ^{at venus} 00:03, 12 March 2011 (UTC)

Actually 'the diversity' still seems to imply a singular source. I'm not trying to advocate a significant change here so, how about simply replacing "This process has produced all the diversity of living organisms." to:

This process has produced diversity in living organisms.

or even:

This process is the primary source of diversity in living organisms

Then we are no longer making the claim that we know for sure that it is the only source of diversity. Puppetx (talk) 23:59, 11 March 2011 (UTC)

Okay, what other processes have produced diversity? -- Kim van der Linde ^{at venus} 00:05, 12 March 2011 (UTC)

There are plenty of things which could have happened, but we have no reason (or sources) to indicate that they have. Our sources indicate that Evolution is responsible for the diversity of life, and that alone is what we can represent. Further, it is important to emphasize and contextualize that notion fully within the text. We can not indicate, or even imply, that any other method could be responsible for diversity without a reliable source indicating as much. As far as I'm aware, we have no such source which passes WP:Weight concerns, so this cannot be a factor in phrasing the sentence.   — Jess· Δ♥ 00:06, 12 March 2011 (UTC)

Thanks to everyone for taking the time to reply. I'm just curious, why is it we can't imply that something else could have created diversity without evidence, but we can imply that nothing else created diversity without evidence? Isn't proving a negative (nothing can create diversity except evolution) harder to prove than a positive (evolution creates diversity)? It just seems to me that if abiogenesis occurred on earth and somewhere else in the universe the odds of that life being identical are quite slim. If it isn't identical than it is diverse. Would this line be changed if abiogenesis were proven and the resulting life included random or sudo random DNA stands? Puppetx (talk) 19:01, 13 March 2011 (UTC)

Because that would be nonsense. Current evidence strongly suggests that Abiogenesis occurred three point something billion years ago, and that evolution, i.e., "descent with modification (due to an imperfect copying system)," is what caused, and still is causing biodiversity. Trying to say that GODDIDIT or DESIGNERDIDIT, while simultaneously handwaving away the urgent need to support such a claim with verifiable evidence is unfair, dishonest, and not science.--Mr Fink (talk) 19:19, 13 March 2011 (UTC)

Puppetx there are lots of different traditional and/or religious explanations about how life began. Many of these are both notable and verifiable and can therefore in Wikipedia in appropriate articles, and with appropriate wording to explain what types of stories these are, but this article is about a mainstream scientific subject and is already quite full. Just out of curiosity do you think that Wikipedia articles about the book of genesis should as a point of principle be made to include mention of every single other type of religious or traditional explanation which disagrees with it? Religious and traditional explanations are different from scientific ones partly because they do not even aim to be convincing. They are just supposed to be accepted. So there the number of variations on the creation of life theme is virtually unlimited. I presume you only want special treatment for one of those?--Andrew Lancaster (talk) 19:46, 13 March 2011 (UTC)

Goddidit is a red herring here. I don't see where Puppetx implies anything of the sort. If there were multiple instances of abiogenesis on Earth, then some of the existing diversity may come from the disparate lineages, unless they all went extinct but one. Since we know so little about actual abiogenesis, it does not make sense to issue pronouncements one way or the other. Regarding "all" diversity, I do see some ontological hairs being split, so I'll just sit back and watch the rest of the show. __ Just plain Bill (talk) 20:06, 13 March 2011 (UTC)

I am an atheist. The position of universal common descent is one I defend. I do not disagree that evolution is practically _the_ source of biodiversity. I'm just grasping at the scientific accuracy of this statement. For those in disagreement, can _someone_ provide citation for the claim that abiogenesis can't create "disparate lineages"/diversity, or explain to me how I'm misrepresenting this sentence? This is not a claim I'd like to make/defend in formal debate, specifically because of the criticism I'm bringing up. I would expect to be laughed at if I responded with any of the posts of disagreement so far. Puppetx (talk) 21:32, 13 March 2011 (UTC)

Let me add that my suggested wordings are poor, I agree. Which is why I've made this post, to engage the community to come up with a better way of saying it. A way that doesn't claim that we have evidence to present that there is no other source of biodeversity than evolution. Heck, isn't genetically modifying crops is a source of diversity that is not evolution? I swear to the FSM if I get 1 more Poe telling me that "god didn't do it bro"... Puppetx (talk) 21:38, 13 March 2011 (UTC)

@PuppetX, if the word "all" was removed from that sentence, would you be satisfied? That word is not critical and removing it would not make that sentence any less accurate. mezzaninelounge (talk) 21:51, 13 March 2011 (UTC)

I strongly object to removing that word, because it does change the meaning. -- Kim van der Linde ^{at venus} 22:30, 13 March 2011 (UTC)

PupetX, artificial selection and other human induced methods strictly are a form of evolution, just by a specific natural cause, humans. Anyway, as long as we have no evidence for anythimng else than evolution, I think changing the wording is inappropriate. -- Kim van der Linde ^{at venus} 22:30, 13 March 2011 (UTC)

@mezzaninelounge: Yes, I think removing the word "all" would make the sentence much more defensible.

@Kim van der Linde: Why is the word inherited used so frequently in the definition of evolution? Genetic engineering produces traits that were not inherited, into life that often cannot reproduce? It is life, its traits weren't inherited, it can't produce offspring that would inherit those traits. Are you suggesting we remove the word inherited from the definition of evolution? "the change over time in one or more inherited traits found in populations of organisms." This seems to exclude genetic engineering, especially when the result isn't viable. Puppetx (talk) 23:02, 13 March 2011 (UTC)

Not all genetically engineered lifeforms are sterile: genetically engineered bacteria are more than capable of passing on their modified traits to their descendants and other bacteria. And many genetically modified crops and livestock are more than capable of reproducing, unless they have been deliberately sterilized. Furthermore, to exclude genetic engineering from Evolution is just quibbling.--Mr Fink (talk) 23:25, 13 March 2011 (UTC)

Currently, the sentence reads, "this process has produced all the diversity of living organisms." At the moment, it is not clear if the term "process" refers to evolution by natural selection, evolution by genetic drift, mutation, or a combination of these processes. That is the critical problem. Based on the sentence that follows it, I'm assuming it refers to evolution in general. So I suggest that the sentence be modified to read:

"Evolution has led to the diversification of living organisms" or "Evolution has led to the diversification of all living organisms"

If the word "all" is included in that sentence, it would still be correct because we are referring to evolution in general and not a specific process of evolution. mezzaninelounge (talk) 23:57, 13 March 2011 (UTC)

Either of these is satisfactory to me as it removes the burden of proving that there is no other process in the universe that can produce diversity except evolution. Am I wrong in believing that the absence of evidence to the contrary shouldn't be accepted as evidence in favor? Puppetx (talk) 00:30, 14 March 2011 (UTC)

No, that is not wrong. Absence of evidence is not evidence of absence. That said, it is very difficult to find evidence to support explanations that does not in some way involve evolutionary processes. :D mezzaninelounge (talk) 00:41, 14 March 2011 (UTC)

Fantastic/thanks. We are entirely in agreement. =D Puppetx (talk) 01:57, 14 March 2011 (UTC)

I am in perfect agreement here to. es.p "Absence of evidence is not evidence of absence." I would put it this way: we can not make a claim in the article that we cannot verify, even if it seems extremely unlikely for it to be otherwise. that would just be plain unscientific. (in addition to being contrary to policy. WP:VERIFY) Kevin Baas^talk 14:32, 14 March 2011 (UTC)

Really Evolution "explains" the diversification of all organisms both past and present. Why ignore past life and the geologic and fossil record? Seems to ignore past life. In simple terms what you are really saying is descent with modification (evolution) explains the diveristy of life both past and present. All life has descended from a universal common ancestor-an organism(s) or gene pool that has given rise to all life in a continuum of life from past to present-the tree of life. We shouldn't even be talking about abiogenesis because that is a separate topic and you don't want to confuse the reader. The fact of evolution is the outcome (The tree of life) and the processes of evolution (natural selection, genetic drift, and gene flow are the processes (with a dose of chaos such as extinction events) that mechanistically explain how traits change in a population through sucessive generations, adaptations, speciation, and other outcomes of evolution likely occur. Anyways my two cents. GetAgrippa (talk) 02:56, 16 March 2011 (UTC)

I agree with GetAgrippa. A. Z. Colvin • Talk 03:04, 16 March 2011 (UTC)

This discussion is about a sentence in the lead, which does not mention abiogenesis, Given the new wording, there is no need for such mention. __ Just plain Bill (talk) 03:34, 16 March 2011 (UTC)

I only briefly mentioned it in my brainstorm version to allude to the fact that abiogenesis -- which is not evolution -- might also have been a source of diversity. But i agree that it doesn't really need to be mentioned. and the most recent suggestion looks fine to me. Kevin Baas^talk 12:34, 16 March 2011 (UTC)

"Evolution has led to the diversification of all living organisms" looks supportable to me, and is free from clumsy circumlocution. I like it. __ Just plain Bill (talk) 21:41, 14 March 2011 (UTC)

Daniel...actually, you've stated a logical fallacy. The absence of evidence IS evidence of absence. If I were to follow your logic, it would become impossible to be reasonably certain of anything. I don't have evidence that there is an antique teapot floating above the dark side of the moon. And that's sufficient to state there is no evidence. The same in creationism or any other supernatural act. The absence of evidence is evidence of absence, but most scientists will state that if there is evidence forthcoming, we are willing to review it and possibly change our mind. The biggest problem with that particular logical fallacy is that you end up with the other side making an impossible set of requirements. Like my teapot theory, they would keep changing the rules...oh you can't see the teapot except on the fifth monday of March. Or that it requires a special UV filter. Or it can only be seen by a virgin who has devoted her life to the collection of teapots. The absence of evidence is always evidence of absence. OrangeMarlin ^{Talk• Contributions} 16:15, 25 March 2011 (UTC)

@Orangemartin. That is not a logical fallacy. Absence of evidence is not evidence. How could it be? To suggest that it is would be to make a logical fallacy. See "argument from silence" and "Affirmative conclusion from a negative premise." You're right, it is impossible to be absolutely 100% certain of anything. Which is we use a lot of statistics in science. Unlike religious or mythological statements, scientific statements tend to be tentative and are subjected to change. mezzaninelounge (talk) 16:41, 25 March 2011 (UTC)

@Daniel and Kevin. First, Absence of evidence is always evidence of absence especially when you're looking for evidence. Argument from silence and affirmative conclusion from a negative premise have absolutely nothing to do with my point. And as for Verify...what do you think I am? A noob? Sheesh. OrangeMarlin ^{Talk• Contributions} 23:41, 26 March 2011 (UTC)

@OrangeMartin. It is not. A "nothing" cannot be a "something." Pure and simple. If we were to go by your logic, then radio waves do not exist before Maxwell's equations, which is clearly not the case. They have always existed. Thanks to Maxwell, we were just able to detect them only recently. Again, just because we have not found evidence of something, it doesn't it mean that it doesn't exist or that we have evidence that it doesn't exist. It just means we have not found it or we do not have the technology to detect it. As James Randi said, "you cannot prove a negative." You are right about one thing. Argument from silence and affirmative conclusion from a negative premise are not the points that you were making. They are just the fallacies that you were making. By the way, no one is trying to lecture to you. Also, Kevin's post happens to precede your first post. So please calm down as you are overreacting like a noob. mezzaninelounge (talk) 01:10, 27 March 2011 (UTC)

@OrangeMartin. By the way, this is getting off topic and I believe I have made my point. If you wish to continue with this discussion, then please post your future replies to my talk page. I don't think this has much relevance to the main issue of this talk session. Plus, I doubt the other editors are interested. mezzaninelounge (talk) 01:16, 27 March 2011 (UTC)

Theory of Evolution and revision of terminiology

Because of the constantly evolving nature of the Theory of Evolution, and as it is a theory, it ought to be labeled as such throughout the article. Not having the word "theory" preceding it shows an over-sensitivy to the subject, as if it were feared that it would be disproved. Several theories (i.e. theory of gravity) are still labeled such and without issue. — Preceding unsigned comment added by Paulbraveheart (talk • contribs) 23:30, 26 March 2011 (UTC)

Please see the FAQ. Evolution is a fact, and you misunderstand what constitutes a theory. OrangeMarlin ^{Talk• Contributions} 23:39, 26 March 2011 (UTC)

Gene-environment interactions

It seems that every time I look at this entry the definition has changed. Once again the current definition is factually incorrect. Characteristics that result from gene-environment interactions are not inherited. Obesity, exercise-induced muscle mass, and accidental trauma are examples of such interactions, none of which are passed on to future generations. Once again there is a sense that this particular entry attracts a great deal of interest. However, the definition of evolution should not be a moveable feast. EMT (Cardiff)131.251.142.18 (talk) 08:31, 31 March 2011 (UTC)

I am sure all people watching this article and working on it agree about the importance, but this first sentence gets a lot of discussion. Obviously the logical point you raise is a bit trickier than you make it out to be. The text does not actually say what you think it says. It does not say that "gene-environment interactions are inherited". It says that "Inherited traits ... result from gene–environment interactions". This sounds correct to me? --Andrew Lancaster (talk) 08:47, 31 March 2011 (UTC)

The exact sentence is: "Inherited traits are particular distinguishing characteristics, including anatomical, biochemical or behavioural characteristics, that result from gene–environment interactions." Which without the modifiers reads: "Inherited traits ................. result from gene–environment interactions." This is incorrect. EMT (Cardiff) —Preceding unsigned comment added by 131.251.142.18 (talk) 09:24, 31 March 2011 (UTC)

The characteristics of organisms arising from interactions with the environment are known as "acquired characteristics" and the theory proposing that these are heritable is known as Lamarckism, and is not now considered to be a valid theory of evolution. Whilst discussion on the subject of evolution should of course be encouraged, constant, often inaccurate changes to the basic definition cannot surely be a good thing? EMT (Cardiff) —Preceding unsigned comment added by 131.251.142.18 (talk) 10:34, 31 March 2011 (UTC)

an interesting note on lamarkian evolution: in computer science there is what's called a memetic algorithm - a fairly recent development - which combines traditional genetic algorithms w/online learning such as and adaptive artificial neural net. the result is you get the local search power of online learning and the global search power of genetic algorithm. the synergy of the two make for significantly faster convergence than either alone! (even though it's not an accurate model - it sort of combines nature and nurture into one.) Kevin Baas^talk 13:07, 31 March 2011 (UTC)

131.251.142.18 I do not read it that way, although maybe if it can be read that way it should be improved. On the other hand, there are certainly no words saying anything about acquired traits becoming heritable in the text you are criticizing?--Andrew Lancaster (talk) 15:09, 31 March 2011 (UTC)

I'm not sure how it can be read any other way. The text says that inherited traits result from gene-environment interactions; in other words gene-environment interactions are the cause of inherited traits. Whether it is mentioned in the text or not, what is described in the article is Lamarckism, and it is a long way from the consensus definition of evolution.

EMT (Cardiff) —Preceding unsigned comment added by 131.251.142.18 (talk) 08:54, 1 April 2011 (UTC)

EMT, what if it was phrased as "Gene-environment interactions can modify the expressions of inherited traits or phenotypes ... ". Would that clear up the misunderstanding? mezzaninelounge (talk) 13:07, 1 April 2011 (UTC)

The distinction should be made that gene-environment interactions influence the phenotype. The "expression" of inherited traits is influenced by gene-environment interactions. That covers simply lacking an appropriate amino acid to epigenetic influences.OK beat me to it-mezzanine. GetAgrippa (talk) 13:11, 1 April 2011 (UTC)

I agree with both of the last comments. The bottom line is that if the second sentence is going to be a definition of "inherited traits" then the phenomenon of "gene-environment interactions" has no place in this sentence (indeed has nothing to do with it). EMT (cardiff) —Preceding unsigned comment added by 131.251.142.18 (talk) 13:20, 1 April 2011 (UTC)

OK, how about this revision:

"Inherited traits are particular distinguishing characteristics, including anatomical, biochemical or behavioural characteristics. The phenotypic expression of these traits can be influenced by gene–environment interactions."

mezzaninelounge (talk) 20:18, 1 April 2011 (UTC)

That is much better. I would add a short phrase on the end of the first sentence as follows: Inherited traits are particular distinguishing characteristics, including anatomical, biochemical or behavioural characteristics, that are passed on from one generation to the next. The second sentence is superfluous but is not, at least, incorrect. EMT Cardiff —Preceding unsigned comment added by 131.251.142.18 (talk) 09:56, 5 April 2011 (UTC)

Done. As for the second sentence, I agree. I'm tempted to remove it but no harm no foul leaving it there either. mezzaninelounge (talk) 16:34, 5 April 2011 (UTC)

gravity vs evolution

Why does the law of gravity have alternative theories and evolution does not? Overseer19XX (talk) 20:13, 3 April 2011 (UTC)

Because there are no scientific alternatives to evolution.... -- Kim van der Linde ^{at venus} 20:21, 3 April 2011 (UTC)

Yes, there has been no evidence found to suggest any alternative explanations to evolution. A lot of people don't realize that the scientific community is all ears when it comes to alternative explanations. The only catch is that you need evidence to support the proposed alternative.--Mr Fink (talk) 20:27, 3 April 2011 (UTC)

As we jokingly say, if you can prove that an alternative to evolution is valid, it is an instant Nobel Prize. -- Kim van der Linde ^{at venus} 20:40, 3 April 2011 (UTC)

Now, in fairness, this article does show alternative explanations, such as nearly neutral theory. Of course all accept the basic fact of evolution occurring, in the same way that alternative explanations of gravitation accept the basic fact that gravity occurs. Not sure what's meant by "the law of gravity" as that's a redirect, and of course explanations of gravity aren't as well established as modern evolution theory, but in some ways there's a similarity in there being various refinements of the basic explanation. One thing I notice is that the gravitation article doesn't give any attention to religious views such as intelligent falling, but that's really a matter of religion rather than science. . . dave souza, talk 22:46, 3 April 2011 (UTC)

There is no "law of gravity." There is a theory of gravity. The OP fails to understand that "theory" is equal to fact in science. Furthermore, a theory describes a synthesis of observable phenomena, so it's testable. The theory of Evolution is a fact. The best we could discuss is that there are various mechanisms, maybe more than just genetic drift and natural selection. In the gravity article, the theory of gravity is not under discussion, it exists. What is being discussed are the various theories of relativity, which describe the mechanism of gravity. There are no alternative to evolution. But if there is scientific evidence, I'm sure we would discuss it. OrangeMarlin ^{Talk• Contributions} 00:25, 4 April 2011 (UTC)

Hi OrangeMarlin, I get your point, but it might not be the best of explanations for those who have trouble understanding it. People really do talk about a "law of gravity". I think the confusion comes from people taking language, messy word-use which has resulted from accidents of human history, as if it is reality. The word use history can in any case be explained: modern science does not actually accept the concept of absolute knowledge, and so "laws of nature", as the term was being newly promoted in Newton's time, are always open to being questioned. A law of nature in modern physics is therefore to be understood as any strong pattern in nature. So there is nothing higher than a theory in modern science, except a better theory, and the question is always concerning how strongly the theory is supported by facts. And looked at this way, evolution is one of the most secure laws or theories modern science has.--Andrew Lancaster (talk) 06:02, 4 April 2011 (UTC)

The question is not the validity of evolution, but the lack of alternative theory's. In a religious Creationism wiki there is a link to creation-evolution controversy. I believe that is also valid here as a link and text. This would help bring this wiki in line with NPOV and bring the two into symmetry. Otherwise remove the "scientific part" from the "religion" wiki. — Preceding unsigned comment added by Overseer19XX (talk • contribs) 14:03, 4 April 2011 (UTC)

Already here, if anything going beyond NPOV in giving any weight at all to this pseudoscientific religious argument. . . dave souza, talk 15:12, 4 April 2011 (UTC)

Sorry, creationism is NOT a valid scientific theory as it is not based on science but religion. -- Kim van der Linde ^{at venus} 15:39, 4 April 2011 (UTC)

Not just the fittest

For consideration for inclusion. Mutation resilience allows the fittest, and the not so fit to co-exist. - RoyBoy 03:27, 6 April 2011 (UTC)

Oh yes, let's use something from Kurzweil that science illiterate. Instead, I went to the original article. Beardmore RE, Gudelj I, Lipson DA, Hurst LD (2011). "Metabolic trade-offs and the maintenance of the fittest and the flattest". Nature. doi:10.1038/nature09905. PMID 21441905. Retrieved 2011-04-05. {{cite journal}}: Unknown parameter |month= ignored (help)CS1 maint: multiple names: authors list (link) And do you know what the article said? And do you know what Darwin said? The article says that both fit and "unfit" (and don't think of this as a matter of cardiovascular fitness) exist at the same time. And Darwin never said that only the fittest survive. What Darwin said was that the fittest had the greatest probability of surviving to the next generation. Over thousands of generations, the average genotype of the population will move towards the "fittest." But, it would be naieve to believe that the whole genotype of a population is exactly the same. So why wouldn't the flattest (words of the Nature article) make most sense, since it gives the broadest amount of genotypes to deal with an environment. But the article also says the more complex the organism, the more the tradeoffs between fitness and not so fit become a bad strategy. You see, the article makes sense for bacteria. Not so much mammals. But hey, let's rely on blog posts from the illiterate. OrangeMarlin ^{Talk• Contributions} 04:51, 6 April 2011 (UTC)

Translation: "Been there, done that with more competent, more reliable sources." Also, laypeople tend to wrongly assume that the "fittest" in "survival of the fittest" always refer to some sort of athletic, herculean, uber-organisms. The definition of "fittest" always changes in relation to the relevant situation and environment.--Mr Fink (talk) 05:22, 6 April 2011 (UTC)

Yeah, I have a obese, but wealthy, friend who gets all the gorgeous girls. Obviously, selection has favored him in some manner. I imagine it's the AMEX card. Critical thinking is a lost skill these days. OrangeMarlin ^{Talk• Contributions} 05:32, 6 April 2011 (UTC)

Really "fittest" or "survival of fit" shouldn't be anywhere in this text-we should be talking about "fitness" and reproductive success. SSpencer coined the term and it always used incorrectly and just creates confusion. Evolution is often a compromise. I remember reading about garter snakes evolving in a sort of arms race with newts that use tetrodotoxin as a defense. The garters have evolved a resistance to withstand doses of TX that would kill a hundred people. The problem is the adaptation has also altered their voltage gated sodium channels and they are slower after eating the toxin. Thus they have slower reflexes, and they are slower after ingesting a TX rich meal- making them more prone to a predator. Tit for tat. GetAgrippa (talk) 22:31, 6 April 2011 (UTC)

One of the classic evolutionary stories of fitness is sickle cell disease. Even though the disease is obviously disadvantageous, why did it stay around? Because heterozygous genotype confers resistance to malaria. So the less fit genotype is actually more fit. These things don't show that evolution is wrong, it really establishes how robust natural selection is. BTW, with regards to the garter snakes, wouldn't the blood level of tetradotoxin be so high that predators would avoid the snake? Maybe over time predators would start avoiding these slow garter snakes. And nice to see you GetAgrippa...long time! OrangeMarlin ^{Talk• Contributions} 16:58, 7 April 2011 (UTC)

Comic strip version... hat tip. . . dave souza, talk 23:09, 6 April 2011 (UTC)

Dammit Dave....I spit up my coffee! OrangeMarlin ^{Talk• Contributions} 17:04, 7 April 2011 (UTC)

Good to see you are still about Orangemarlin-ole friend. Heterozygote advantage is an excellent example. Interesting note on the garter snakes too. That is just what it is all about-evolution can work in ways that seems illogical or counterintuitive, and in ways we just don't pick up on. GetAgrippa (talk) 17:12, 7 April 2011 (UTC)

One of the biggest fallacies of creationist logic is that they assume that evolution is predictive. Evolution is filled with unintended consequences that sometimes provides an advantage, sometimes a disadvantage. BTW, if I were a garter snake, I'd stick with mice or something. OrangeMarlin ^{Talk• Contributions} 17:19, 7 April 2011 (UTC)

I'm hoping to evolve an Amex card to attract viable mating opportunities as your friend. hee,hee,hee. GetAgrippa (talk) 18:05, 7 April 2011 (UTC)

Since Darwin and that whole generation didn't know anything about inheritance, their ideas about the "fittest" individuals doesn't really have much to do with our modern understanding of selection, which acts on a single genetic locus (modulo linkage). The reproductive fitness of an individual is an agglomeration of all the different fitness effects of all the genes they possess (and how much they worked out/ate/fucked, or whatever), but what leads to successful propagation of a trait is the probabilistic effect across a number of individuals. From this gene-centric perspective, the individual's actual fitness isn't really that important - it's the fold-increase in fitness the gene confers. Graft | talk 22:42, 7 April 2011 (UTC)

Edit request from A.Kazimierz, 28 April 2011

Please add an item in 'See also': http://www.dissentfromdarwin.org/ There is an explanation for this addition in the webpage itself: "We are skeptical of claims for the ability of random mutation and natural selection to account for the complexity of life. Careful examination of the evidence for Darwinian theory should be encouraged." (index page, frame on the left). There also is a list of the scientists which seems capable of holding the ground against the protection of this entry in Wikipedia (at the time of this edition the link to the list was http://www.discovery.org/scripts/viewDB/filesDB-download.php?command=download&id=660).

I kindly ask for a reply to my request (a.kazimierz@interia.pl)

A.Kazimierz (talk) 16:49, 28 April 2011 (UTC)

That's already covered in the #Social and cultural responses section, to meet WP:WEIGHT policy this overview of the science does not give attention to specific creationist religious claims such as the dissent from Darwinism petition which are covered, in majority expert view context, in their own articles. . . dave souza, talk 17:09, 28 April 2011 (UTC)

Interesting list of scientists who don't support evolution. But the AIDS article supports HIV as the cause of AIDS-as the vast majority of scientist support that argument. There is no mention of the Duesberg hypothesis which is supported by a minority of scientist. Similar problem here. The vast majority support evoution and the literature has few peer reviewed exceptions. If the list of scientist are "capable of holding the ground" then they are welcome to contribute. After all this is an anybody can contribute. The article isn't protected but there are numerous editors (many experts in evolution) that you have to be "capable of holding the ground" against with peer reviewed support and arguments with merit. A list of scientist who are "skeptical" is just anectdotal opinion without sound evidence and arguments-it doesn't matter their occupaton. Regards GetAgrippa (talk) 20:39, 30 April 2011 (UTC)

Most of the "scientists" on the list aren't real scientists. Some are engineers (which isn't a natural science, it's an applied science), some have really bogus degrees, and some are physicians (same point as engineers). Don't be too impressed. Don't forget Project Steve. MastCell (talk · contribs) once wrote that sometimes scientists get involved in fields outside of their training and research, and they tend to be arrogant in their beliefs. Like Jane Goodall stating that Sasquatch actually exists. Or the AIDS denialists. And as I always say, science isn't a democracy with a "vote". But if it were, the creationist "scientists" would be a tiny little minority. Oh, they are. OrangeMarlin ^{Talk• Contributions} 21:59, 30 April 2011 (UTC)

I agree. As I understand, polls indicate the majority of Christians don't really have a problem with evolution-nor Judaism or Islam. What drives the skepticism? It is difficult to deny the Morphologic (fossil, comparative anatomy), Biochemical,Genetic, Behavioral evidence. Now if you ask are there unresolved issues, well of course, science is a process. Protist still remain a paraphyletic enigma. China keeps finding weird fossils from Archean and Protozeroic era that are difficult to classify. Lots of arguments between anthropologist over this and that. But that is the process of science. Evolution is still the glue of all biology and medicine, and relays the story of life on our planet. GetAgrippa (talk) 23:03, 30 April 2011 (UTC)

Dealing with Creationism

One point, I had to say, was that the article refers to Creationism as 'The Creation Myth', now while I'm not trying to start a debate here, I was just wanting to point out that saying that is a non-neutral approach, because there IS proof for Creationism, so labeling it a 'myth' is a bias. Please don't ban me, I'm just trying to help.Xirandraymur (talk) 05:28, 21 January 2011 (UTC)

If there was evidence for a literal interpretation of the King James' translation of the Bible, people would have seen and documented such evidence already. Plus, Wikipedia is not neutral, it is biased towards documented, verified evidence. Furthermore, no one here has any intention of banning you, given as how you do not appear to be intending to vandalize the page.--Mr Fink (talk) 05:32, 21 January 2011 (UTC)

Oh. I suppose. I just have this Creationist friend, and he was like 'you guys haven't found any of the missing links yet'. We have found those, right?Xirandraymur (talk) 05:37, 21 January 2011 (UTC)

Yes, missing links have been found. It is a misnomer to refer to them as missing links for this reason - they are no longer missing. It might also interest you to know that the proper defenition of a myth is basically a supernatural story often having to do with the origins of a people or religion that may or may not be true. No implication of truth or falsehood is implied by the use of "myth."Farsight001 (talk) 06:05, 21 January 2011 (UTC)

You can read more about creationist claims and scientific responses to these at Creation-evolution controversy.--Charles (talk) 09:56, 21 January 2011 (UTC)

Agree with Mr Fink and others. Wikipedia aims to be neutral, but it also has other policies such as verifiability. What we produce should meet both specifications and is not neutral in any absolute sense. Verifiability "biases" us towards mainstream published works in all fields, and it does not give us much room for giving special sensitivity to myths, except to describe them when they are notable and verifiable. If we started having to accept all possible explanations anyone can come up with for everything then obviously this would include a lot of myths, and not just Christian ones.--Andrew Lancaster (talk) 11:03, 21 January 2011 (UTC)

Creationists do have evidence for their claims. Example: The Institute for Creation Research puts out tons by the way of evidence, such as The Genesis Flood: The Biblical Record and Its Scientific Implications by John C. Whitcomb and Henry M. Morris. And besides, the theory of macroevolution through natural selection isn't verifiable, because it takes too long to conduct an experiment of it. --Joshuajohnson555 (talk) 04:37, 10 March 2011 (UTC)

I personally agree with everyone that creationism is a myth. At the same time however, the term is quite provocative. WP list the Genesis Creation Myth as the Genesis creation narrative. I have no preference either way, but I would add that calling it a narrative and not a myth does not in any way imply that it is true. It just means that the myth is a story. My two cents. mezzaninelounge (talk) 14:51, 21 January 2011 (UTC)

So what missing links have been found? I'm still a little fuzzy on that. 174.70.43.177 (talk) 15:45, 21 January 2011 (UTC)

Couple starting points for you, Evidence of common descent and Transitional fossil. — raekyt 16:28, 21 January 2011 (UTC)

Here's a good resource: http://tolweb.org/tree/ thx1138 (talk) 22:25, 26 January 2011 (UTC)

I have to agree with OP. I understand that Wikipedia is all about documented, verified evidence, but those who believe the "Creation Myth" (myself included) believe there is plenty of that in support of Creation. I'm not here to argue against evolution or the data contained in the article, simply to say that "myth" is a subjective term and should be replaced by something more neutral, like "story" or "account", to better reflect the on going debate between the two. Especially since the article that the link redirects to is called "Genesis Creation Narrative", not myth. 71.170.115.107 (talk) 03:35, 8 February 2011 (UTC)

Please do elaborate on this evidence you speak of, and Mary appearing in toast doesn't count... — raekyt 03:47, 8 February 2011 (UTC)

This is not the place for a debate between individuals. If this is relevant to Wikipedia then mainstream biology needs to treat it that way. It does not matter what we believe as individuals.--Andrew Lancaster (talk) 07:39, 8 February 2011 (UTC)

If Wikipedia is going to refer to it as the "creation myth" on the evolution page because that's how biologists view it, then I guess we can refer to it as the "evolution myth" on the Creation page since that's how Christians view it... 129.107.237.4 (talk) 02:47, 9 February 2011 (UTC)

No, we can not, as that would be lending undue weight to a fringe viewpoint. Unless you want us to also do things like refer to the "Holocaust Myth" or the "Slavery Myth" or the "Vaccination Myth" Until then, please stop soapboxing.--Mr Fink (talk) 02:58, 9 February 2011 (UTC)

@129.107.237.4 That's a red herring. I've never seen a Christian refer to it as the "Evolution myth" and it is certainly not mainstream Christian to reject modern science as wrong. Christians going on a plane trip or getting medical advice show what they really trust to be right about things in "this world" - ie modern science. Creation myth is a general term which is not religion specific. No other general term comes quickly to mind but if someone can think of one, by all means use it. ("Traditional creation stories"?) It is not the aim to insult Christians. Speaking in general and neutral terms is important. It is not to be assumed that Wikipedia editors consider Christianity to be the only religion out there, and obviously when you remember there are many of them it makes more sense that we simply can't write "in universe" in each article about each religion, because all religions agree that all (other) religions are wrong. It is the nature of faith based religions that they will always be insulted by neutrality, and for WP neutrality is an important policy. That is the real cause of the problem.--Andrew Lancaster (talk) 09:51, 9 February 2011 (UTC)

Question from a newbie. Why is the term 'genesis creation myth' in this article linked to the 'Genesis Creation narrative' article. Regardless of how you feel about either theory, shouldn't there be an element of uniformity among terms?--Jazzcat23 (talk) 15:25, 12 February 2011 (UTC)

I see no special reason to have uniformity to this extent. A selection of words that sound nice as an article title do not necessarily fit in a running text.--Andrew Lancaster (talk) 08:59, 13 February 2011 (UTC)

Jazzcat...Evolution is a theory in science, which means it's pretty a fact. Creationism is an invention with no evidence whatsoever. Don't create a false equivalence, because Evolution is real science and creationism is an invention necessary for uneducated Bronze Age goatherders. It's a myth. A fairytale. LeftCoastMan (talk) 00:50, 27 February 2011 (UTC)

The New Oxford American Dictionary, 2nd edition has two definitions for "myth." The first is "a traditional story, esp. one concerning the early history of a people or explaining some natural or social phenomenon, and typically involving supernatural beings or events." The second is "a widely held but false belief or idea." It appears to me that most English-speakers commonly interpret the latter as the most common. Therefore, we should either change the term "myth" to "narrative," "story," or "account" or other related words, or put a footnote saying that "myth" does not necessarily mean that the story is false, and include the first definition. --Joshuajohnson555 (talk) 04:37, 10 March 2011 (UTC)

Unless you have evidence that says it isn't false, which you don't, then myth stands. It is a widely held false belief. We're done here. LeftCoastMan (talk) 16:48, 13 March 2011 (UTC)

There is a much proof for Creationism as there is for Evolutionism. There are many scientists and archaeologists that support both theories. The only reason why anyone would call it a myth is if they were intentionally trying to poke it in the face of people who believe in Creationism. If for no other reason, just change the wording to satisfy Creationists as the wording is only relevant to them. This is so WP:Fringe to link to an article and change the name of the actual article in the link just to support your opinion. It shows how immature some people are and it is obvious to me that we should simply call it a narrative like Wikipedia calls it. Why in the world would you not?--Jacksoncw (talk) 15:42, 25 March 2011 (UTC)

You have been badly misinformed about creationism. thx1138 (talk) 16:00, 25 March 2011 (UTC)

When the creationists can provide peer reviewed scientific evidence for their claims, then wikipedia and its editors will be more than happy to change the relevant articles. Can any of the creationists please provide a link to a peer reviewed study from a reliable source that provides *real* evidence? Thought so. That is why this article reads the way it does; yes it's biased...towards those claims that are backed by EVIDENCE SuperAtheist (talk) 18:10, 8 April 2011 (UTC)

You "believe" there is evidence? Either there is or there isn't. The irrefutable fact remains that there is no objective, verifiable evidence for creationism. None whatsoever. The fact that somebody wrote a book about it is NOT evidence. —Preceding unsigned comment added by 178.208.213.145 (talk) 13:12, 17 April 2011 (UTC)

It seems "a book says it" and "empirically obvious" is a similar argument for both sides-just antithetical. But offering an argument "just because I say it so" is bizarre, also ad hominems aren't an argument at all. Seems juvenile and illogical. So I presume you believe in little snow fairies or some other supernatural phenomenon is responsible for each unique snowflake? All kinds of self assembling and spontaineously assembling molecules with beautiful order like buckyballs. But just ignore that I guess. Your argument is that because I'm too lazy to "seek and ye shall find" to try and understand and explore the universe I'll just duck the issue by evoking supernatural means. Even the Moses frog plaque is not really a supernatural event because there are numerous documented cases of raining frogs and even fish too. And this can be scientifically addressed. Because it wasn't necessarily supernatural doesn't negate the impact and liturgy of the bible story. The bible and science agree on the "bang" and a beginning of universe so I don't understand that argument (seems naive). Read up on Georges Lemaître and you'll see a person of faith promoted the "bang" against all scientific dogma of an infinite and always present universe as he balked to a skeptical Einstein. I agree there is an ordered, beautiful, and an incredible universe but wouldn't your argument be that God planted this drive and desire to understand the atom, life, the universe. Christians believe God allows all these things to occur so wouldn't that generate the argument because evolution exists it is part of God's plan. You can't argue it is "Satan" because Satan has been defeated that is a "dead" argument-chasing rabbits. Right? I don't mean to mock you but wake up dude. Your going in circles. Regards GetAgrippa (talk) 03:20, 5 May 2011 (UTC)

Disappointed again

As someone who has taught evolution for over a decade, and used to contribute to this article before deciding I had no more time to argue with every half-informed editor who felt the need to be heard and disrupt the process, I must say that the current organization of this article is probably the worst I have seen it in over 5 years. It is really a shame that a topic of such fundamental scientific importance as evolution cannot be covered in a well-written, well-organized article, and then simply LEFT ALONE for the most part. The wiki process does not MANDATE edits to be made incessantly and eternally -- but instead, due to busybody editors whose pastime it (apparently) is to rewrite and reorganize and revise ad infinitum, with no satisfaction or end in sight, this article itself continuously evolves, but certainly not in a way that has improved it. More than probably any other article I know on Wikipedia, this evolution article resembles a monstrous, creaking ship cobbled together out of sticks and scraps by a bunch of independent hobbyists who know precious little about boat-building. And every time I check in to peek at it again -- usually wincing -- the re-arrangement of sticks and scraps is different, but it is still a sinking ship. Too many cooks spoil: everything. It is unfortunate that every good editing effort that ever improves this article will surely, eventually, get washed away by deleterious mutations... 218.248.64.164 (talk) 07:28, 24 April 2011 (UTC)

This translates into two words "I'm disappointed". Talk pages are meant for constructive suggestions. Materialscientist (talk) 07:43, 24 April 2011 (UTC)

Fair enough. The constructive suggestion is: it IS possible for an article to be of high quality, and not NEED many more frequent revisions. I suggest that this editing group work toward that goal, rather than using the article as an editors' playground. I offer this suggestion as someone who, at one time, spent a lot of constructive time with other knowledgeable editors here going through the arduous, tedious process of consensus, over many many months, which for a short period of time actually resulted in an article that was not perfect, but had many sections that were accurate, clear, and did not need revision. Now, the article is a tremendous mess again, very clumsily written, with poor organization and no flow whatsoever. I think it is a fair and constructive question -- albeit a difficult one -- to ask: what is the point of working hard and collaboratively to produce a quality article, when it will just eventually get torn apart and rebuilt over and over and over and over again, for no good reason other than the fact that restless editors want something to do? 218.248.64.177 (talk) 13:09, 24 April 2011 (UTC)

I beg to differ, most of the contributors to this article have a genuine interest in improving the article in both scope and depth of coverage. Just because an article is FA, doesn't mean it's "done". In fact, the standards for FA have become much more rigorous since 2005; the article has required improvement in order to keep its status as one of the best articles on Wikipedia. If you want an article that is more simple and more like the one that "you wrote" and originally passed FAR in 2005, maybe go to Introduction to Evolution. Perhaps, then, after you're done reading that, you could give us "independent hobbyists" some suggestions to improve the article? Mildly Mad^T_C 14:06, 24 April 2011 (UTC)

The road to Hell is paved with good intentions. I do not doubt that most of the contributors here have a genuine interest in improving the article, and think that they are. The problem is that they eagerly strive to do so even in cases or sections where improvement is not needed. The result is a big, messy sandbox of editing that never reaches a stable equilibrium of quality. "Be Bold" need not be cheerfully encouraged when an article is already of high calibre. Yet it seems that many Wikipedia editors think it's inconceivable that, in fact, a largely-finished article COULD be produced, one that is a good article and does not need frequent rehashing. Instead, there is this never-ending chaotic delusion of "we are improving the article" -- but if you seriously examine perhaps the last 30 MAJOR revisions of the Evolution article, you'd be very hard pressed to objectively describe how it was meaningfully "improved" over the complete course of those revisions. It has not improved, it has simply continued to mutate. When there is no continuity of editing rationale or meaningful quality control, the whole "authorship by consensus process" becomes an unfortunate circular waste of time, because many editors keep editing simply because they want to, and not because their revisions are particularly necessary.

And: before you dismiss my criticism by playing this tired old card, I will be the first to say that "I" did not write the article even in 2005, or before that -- I was only one of many contributors, and I have no attachment to any particular prior version. As a career-long teacher of Evolution (specifically), I do not long for an article that "I" wrote, I long for a stable, good article that is coherent, well-organized, clear, and easy to read for students who depend far too much on Wikipedia. At times (rarely), this article has had fleeting moments of being just that. But then the article is torn down and rebuilt again for no good reason other than someone's personal desire to do so, and again: I say that an examination of the last few dozen MAJOR revisions will show that it has all been a pointless shell-game of shuffling words in response to current whim -- not a meaningful editorial process of improvement. 218.248.64.147 (talk) 14:43, 24 April 2011 (UTC)

Lots of great editors have contributed over the years but without doubt it has had little stability. Months of methodical consensus building and some progress, but then every new reader finds fault and wants to change the article with a flash all gone. Usually lots of ranting and raving how the article doesn't reflect "true" evolution and what a piece of crap it is. A methodical study of past contributions would likely yield a treasure trove of great ideas and past incarnations. In fact, I would wager that many of the good ideas will likely have been added and removed a number of times. The article needs a vision statement or some kind of foundation that can't be morphed without considerable effort. Such a rich literature of evolution just the last ten years is an eye opener for the novice. Whether we academics like it or not people really rely on Wikipedia nowadays. I probably get more readers from contributions on Wikipedia articles than all my peer-reviewed publications. GetAgrippa (talk) 00:15, 27 April 2011 (UTC)

I came to look at this thread on the assumption that someone was making a good suggestion. The anonymous IP is just saying a bunch of words....is there a suggestion in there? I don't think this article is all that bad, considering the way Wikipedia works—fuck the experts, and let anyone with an agenda edit. I don't mind this article. There are lots worse. OrangeMarlin ^{Talk• Contributions} 01:29, 27 April 2011 (UTC)

Yes, GetAgrippa... I agree, although admittedly I can get pretty angry about it. Evolution is so poorly understood by most nonscientists, so badly misrepresented in culture, so regrettably challenged by the hideous ID movement (which is mainly political and not faith-based)... plus, so many people around the world wrongly think of Wikipedia as a good authoritative source of information... it all (along with the unstable and usually deplorable structure of this article) just makes me want to bang my head against a wall. Very very unfortunately, this article is probably the first or only place MANY people will go to read about Evolution, and there is so rarely any clarity here, so rarely a well-structured article that teaches and informs well. There is a huge qualitative difference between peer review and review by anyone and everyone, whether they are scholarly peers or not. As someone who has made an entire career about teaching only evolution, in a number of countries, this Wikipedia article is one of the biggest thorns in my side. I did attempt collaborating as an editor for a long time, but I cannot make monitoring the article part of my daily activities (and of course there are a lot of other quality editors out there -- I do not fancy myself as having the keys to the kingdom -- but I'd venture to say there is an inverse relationship between the quality/knowledge of the editor and the amount of time that editor can spend monitoring the article.)

I only take a little bit of comfort in knowing that my frustrations have been shared by so many other Wikipedia reviewers (see "consensus and hive mind" in the Community of Wikipedia article, and the "Comparative Studies" section under the Reliability of Wikipedia article). Wikipedia is often found to be fairly accurate, but accuracy does not equal skillful writing or a good encyclopedic article if it exists only as a constant haphazard cobbling-together of a bunch of scrap information. I fully agree with my friend Jaron Lanier's opinions on this.... OrangeMarlin, I wish I could cool off and go back to offering enthusiastic, positive suggestions for the article, but knowing that eventually they will just get washed away by the editorial masses unless I guard them like a bulldog, the best suggestions I can offer will be to my own introductory students (around the world) to avoid reading this article. The Wiki model may be fine for writing straightforward articles on simpler topics, but when it comes to producing a quality piece of work about a complex subject like evolution, Wiki just fails miserably by keeping the doors open to everyone. And please don't direct me to the anti-elitist wiki-koolaid about how expert opinions have no more weight on Wikipedia than those of your average citizen. I've heard it all before. Any improvement to the problems I describe can only come from longtime editors who make working on this article part of their daily (or weekly) routine... which I myself am unable to do, mainly because I usually find it to be futile. 117.224.23.194 (talk) 17:40, 27 April 2011 (UTC)

How about a paragraph or two? It's hard to read. And you are confusing the royal crap out of me. You complain about its quality, but then you complain that you don't want to edit. You can't have it both ways. And I completely agree with your comments about experts. On that point alone, I believe Wikipedia will be a passing fad in a couple of years. The difference between Wikipedia and Conservapedia is negligible. It's just that Conservapedia is a lot more honest about its hatred of intellectualism. Oh, now you've got me going. OrangeMarlin ^{Talk• Contributions} 17:50, 27 April 2011 (UTC)

OrangeMarlin, there are no mixed messages here. I have always been willing to help and edit, but never willing to make it a daily/weekly process like you have admirably done for several years here (which I applaud, truly and sincerely). You are one of the ones who could help keep a quality article stable -- I myself do not have the patience to keep fighting for quality and stability, day in and day out. I am apparently one of those rare people around here who thinks that sometimes, an article can reach a state of being well-written and where too many further edits and improvements are neither necessary nor productive. To me that is the whole POINT of editing -- but not here. Here, it is always just a matter of time before eager beaver editors arrive on the scene to tear everything back down without knowing squat about the time, thought, and work that went into it. 117.224.23.194 (talk) 17:57, 27 April 2011 (UTC)

I quit for two years, almost to the day. The only reason I returned was I was frustrated when I would read an article that I had edited, and found that people were making a mess of it. So I guess you're right. The worst thing is that the expert editors just quit, because of frustration, academics, or whatever. OrangeMarlin ^{Talk• Contributions} 18:17, 27 April 2011 (UTC)

To repeat: talk pages are for discussing improvements to the article. Frankly, I agree that one problem facing WP is hoards of people who insist on editin garticles simply because they can and want to. But in my experience an equally serious problem is people editing talk pages to vent their emotions rather than to improve articles. The anonymous editor has written three articles; the same or another anonymous editor has written three more. The continued comments mean one of two things: first, either the anonymous editor simply wants to vent feelings, which is not what the talk page is for. Second, th anony. editor wants to improve the articl, but is being ineffective. Assuming good faith let's just say that the talk so far has been ineffective. Sugestion: please specify one or even two or three specific problems in the article and explain why they are bad. If you really do know the topic and really do find this article so deficient, it actually should be very easy to provide just one or a few examples. Such suggestions are a better use of the talk page, but that is not my main point - my main point is that concrete exmples will communicate your concerns far more effectively. You would convince other editors who would then appreciate rather than resist your comments. Slrubenstein | Talk 18:44, 27 April 2011 (UTC)

Slrubenstein, I do not see much point in offering specific suggestions that may be incorporated now only to get washed away later. My main criticism is about the poor organization of the article, awkward/bad writing, and lack of flow from concept to concept. It would be very hard for a student to really learn about evolution from this article's jigsaw structure. There are also a number of aspects that are poorly described, and occasionally wrong. If you insist, here are just a few:

-An off-topic description of a relatively minor phenomenon (phenotypic plasticity) only 3 sentences into the article;

-Often equating the concept of variation with the concept of allele frequencies (they are distinct concepts);

-Categorically and repeatedly citing "the two processes" in evolution (by what measure are selection and drift more important evolutionary mechanisms than mutation and gene flow?);

-Apparently using the terms trait and allele interchangeably;

-Erroneously suggesting that speciation can result in more than two species (it has always been modeled as a binary process);

-No mention anywhere in the lead (or even in the top half) about the fundamental "first-principle" fact of common ancestry of all organisms;

-Hardly any substantial or clear, simple use of the word homology anywhere in the article (the concept is HUGE to evolution and merits more than a link);

-Oversimplified childish fantasy example of "inheriting a brown eye trait from one parent" (BOTH parents provide alleles, and eye color is a complex multigene trait, not an either/or situation);

-A second out-of-place sentence that seems to imply that all trait phenotypes are determined by gene-environment interactions, when they're not;

-Confusingly invoking the concept of linkage for the first time with asexual organisms (the concept more properly relates to intergene proximity on chromosomes, as is done later);

-Overall too much focus in the article on sexually reproducing organisms (whereas a vast portion of biodiversity, e.g. prokaryotes, is asexual);

-Beginning the explanation of natural selection by saying it "favors genes" (it does not, it favors phenotypes, and thus only indirectly favors genes)...

And that's all in just the top 1/4th of the article. I am too tired to continue just now, and honestly fail to see the point. As important as the above issues are, I don't want to bicker over them because I consider them to be of secondary importance compared to the article's overall poor organization and lack of stability that results from neverending editorial chaos. Inaccuracies and omissions are much easier to correct than an overall lack of editorial vision and continuity. 117.224.23.194 (talk) 19:57, 27 April 2011 (UTC)

Whoever you are, I just want you to know that the list you provided is much appreciated. This is what this article needs. I agree with you that there is a lot in here that is not quite right and could be improved. But the task as you rightly pointed is very daunting. I just hope you don't give up but continue to supply similar lists like the ones above. I will try within a day or two to go through the list and see if we can make appropriate changes to the article. Like you, I too have other more important commitments and will try, whenever I can, to make modest contributions. In the meantime, please keep them (lists of suggestions and criticisms) coming. Oh, if you would like to propose a template or structure for this article, that would be good too. mezzaninelounge (talk) 21:57, 27 April 2011 (UTC)

Mezzanine: In principle I like to help out when I can, but depressingly, I know that even when good article changes are implemented in the short term, eventually they always decay back into sloppy, jumbled garbage in the long term. I just don't think the Wiki concept offers any permanence for sound editing decisions, no matter who they come from. Collaborative editing (or collaborative work of any kind) should always have a goal in mind. However, I frankly think the oft-repeated editing goals of "improving this article" are sham. Improvement must always progress toward (or at least stab toward) higher quality. Here, it doesn't; it is an endless process of round-and-round-we-go-again. An encyclopedia article should not be an eternal conversation of back-and-forth and revisions and rehashings, ad infinitum. Articles on complicated topics like evolution suffer especially from that approach. 117.224.23.194 (talk) 22:15, 27 April 2011 (UTC)

117.224.23.194, but what is the alternative? People are always going to come back here. If you're hoping for a solid peer-reviewed article written by experts in the field, then forget it. It will never happen. This is not a scientific journal and we should not pretend that it is. But if you want something that will help lead people, particularly non-experts, to move on to better sources (e.g., peer-reviewed articles), then Wikipedia articles, as imperfect they are, have fulfilled that role. And THAT is all we can hope for in this chaotic wiki environment. mezzaninelounge (talk) 22:41, 27 April 2011 (UTC)

Mezzanine, I think perhaps you do not know how Encyclopedias are generally used by readers -- especially students. The vast majority of readers will NEVER go to sources beyond this article, and therefore Wikipedia articles need to be of high quality if we are to serve those readers well. I do not plead for peer-review by experts, I plead simply for stability, a bit more permanence of the work that editors do, and a bit more quality control. 117.224.174.181 (talk) 08:04, 28 April 2011 (UTC)

What you're after is to completely change how Wikipedia works, and that's simply not going to happen. This article, even though semi-protected, will always continue to change. Stickee (talk) 08:13, 28 April 2011 (UTC)

117.224.23.194, I think you misunderstood what I said. I agree we need to serve those readers well. But this article will not approach the level of "stability" or "quality" that you find in peer-reviewed articles. In any event, I'm confused as to what exactly your position is. First you say you don't like this Wikipedia article because it is of poor quality, which leads you to advise your students not to visit article. Now you're saying students are going to visit this article anyway and will perhaps use it. As a result, you suggest that we make improvements to it so that it is of high quality. But yet you would rather not help. You're not giving me much to work with here. If you have criticisms about Wikipedia and this article in general, I agree with them, but other than that, there is nothing I can do about it. So once again, are you going to help us or not? mezzaninelounge (talk) 11:39, 28 April 2011 (UTC)

Mezzanine, sum up my position thus: topics as complex as evolution are not well-served by wiki-editing, unless knowledgeable longtime editors who can write well share a vision of getting the article to a high standard where further improvements are rarely needed, and help keep it there through more vigilant vetting of every bold revision. Again, the underlying pathology is not even the quality of the article, it's that no matter what improvements are made, it will only be a matter of time before they get wiki-scrambled back into oblivion. Sorry to be so gloomy about that, it's just been my experience here. The best solution I think is for longtime editors like OrangeMarlin, GetAgrippa, Slrubenstein, dave souza, and a few others like them, to do a bit of archives analysis to examine how the article has changed over the last several years, and see how much of that can truly be called progressive improvement, and how much has just been directionless back-and-forth. I can help a little bit, but I honestly don't have the time to be a regular editor here. But those four (and a few others) seem to, and it seems to me that they are dedicated enough to the article where they, with some effort and help, could collaboratively shape it into a good article and then work a little harder to help prevent major rewrites and reshufflings when they are attempted or proposed. This isn't "owning" the article, it is simply protecting the outcome of consensus when it is reached through hard work. Newer editors who walk-in on a lengthy ongoing process of consensus shouldn't be able to throw a wrench into it so easily and destroy everything that has previously been accomplished by more dedicated editors. Stability of the article can possibly come out of stability of an editorial group, which this article, fortunately, seems to have had. As for whether I am going to help you or not... It is my impression that I already have, and am. 117.224.1.228 (talk) 12:41, 28 April 2011 (UTC)

117.224.1.228, I agree that the four editors that you mentioned should take the lead. But like you and me, they are all very busy, which is why this article right now is in a state of "stasis." So what everyone has been doing at the moment is to remain vigilant and make modest improvements where we can. You seem to have a strong opinion on this issue and a lot on your mind. Rather than express gloom and doom about the lack of stability of this article (which we all agree is the problem) or how its quality will atrophy over time (which we all are trying to prevent), my suggestion is that you channel all your energies into more concrete suggestions/criticisms like the list that you provided above. A list every other day/week perhaps. And if you really want to be helpful, I strongly recommend getting a user I.D. and put this article on your "watchlist." That would go a long well to warning against or preventing unnecessary edits. mezzaninelounge (talk) 13:37, 28 April 2011 (UTC)

117, in response to my note, provided a very constructive list of defects in the article we can work on. there is no point in discussing how wikipedia works. I suggest that people who actively edit this article raise any objections - if they have any - to anon's suggestions, and otherwise, let's go to work making it a better article! Slrubenstein | Talk 19:21, 28 April 2011 (UTC)

Anon (AnneED) here. Has there been prior discussion about merging this article with evolutionary biology? I think the rationale given on that article's talk page is very weak.AnneED (talk) 11:33, 29 April 2011 (UTC)

Another suggestion about this radial phylogenetic tree that is used in a lot of evolution-themed articles here: can it be revised to remove paraphyletic groups such as algae and protozoa? Showing a rough-scale phylogeny that includes "algae" and "protozoa" as taxa belies the fact that they are not phylogenetically valid taxa. AnneED (talk) 11:33, 29 April 2011 (UTC)

117.224.1.228, I am in the process of trying to incorporate the some of the suggestions/criticisms that you gave. Please bear with the slow process. I'm constrained by time and other duties.

AnneED, that merger idea (evolution and evolutionary biology) sounds reasonable. mezzaninelounge (talk) 18:51, 8 May 2011 (UTC)

Explanation of my reversion

First of all, I have never been able to figure out how to revert one in a series of edits with Twinkle, so I apologize for doing it this way. Here are my explanations:

• This edit was just poorly written for an encyclopedia. I was trying to slightly rewrite it, before the edit conflicts went crazy, and I just gave up. I don't really care about the edit per se, just that starting a sentence with "What matters is not....." Sounds like a conversation.
• This edit seems to be in contradiction (or at least removing key parts) of the citation itself. The edit summary gives an inadequate explanation of the deletion. And it seems like a big part of the citation was deleted, but I've noticed some new methods of citation hitting Wikipedia, so maybe I'm wrong.
• This edit made no sense to me, but that's not a reason to revert of course. It just got caught up in the edit conflicts and trying to get everything fixed right. Someone who actually understands what's being said (and it's sad that parts of this article are incomprehensible to me, a person with an advanced degree in biochemistry) can unrevert it.

I'm not sure what was being done here. I reverted, which I don't like to do unless I assume bad faith that the editor is pushing a POV, which is clearly not the case here. Just need some help and an explanation from the editor. I really don't get the second edit at all. OrangeMarlin ^{Talk• Contributions} 21:33, 7 May 2011 (UTC)

I'm concerned that the first edit above is OR. There are no supporting citations. OrangeMarlin ^{Talk• Contributions} 21:40, 7 May 2011 (UTC)

Perhaps Joannamasel and you could work on a "rough draft" here first before making direct edits? Could spare the two of you the frustration. My two cents. mezzaninelounge (talk) 18:24, 8 May 2011 (UTC)

I'm not too worried about Joannamasel's edits. He/she appears to be fairly competent and not pushing a POV, like "natural selection only works on microevolution with no proof of macroevolution." Hahaha. Of all the edits I've ever reverted on Evolution, this was the least troublesome, because it was more an issue of syntax and citations more than anything else.OrangeMarlin ^{Talk• Contributions} 21:32, 8 May 2011 (UTC)

Genetic drift: regressive evolution example

Regressive evolution ((loss of pigments and eyes in cave fish) is given as an example of genetic drift. Genetic drift is by definition not directional. An allele under drift is equally likely to increase as to decrease in frequency. If this were genetic drift, such complex phenotypes would be as likely to appear as disappear in the absence of selection. This is not the case. What is really happening here is biased mutations, where more mutations degrade complex traits than create them. In the absence of selection, you get directional, regressive evolution. I would like to delete this example from the genetic drift subsection.Joannamasel (talk) 22:04, 7 May 2011 (UTC)

Is any evolution truly "directional" in any sense other than that, after it happens it looks like it was aiming at where it ended up? The directional metaphors, such as the term "selection", and the opposed term "random drift" are so widely used that we can not ignore them of course, but they do lead to misunderstandings also and we need to be careful about that. Professional biologists know what they mean when they use these metaphors, but not all the people who read them and use them.--Andrew Lancaster (talk) 08:12, 8 May 2011 (UTC)

Natural selection may be at play here, rewarding the individuals that don't waste resources on pigments. If so, the term "regressive" is misleading, as it's just another example of fitness optimization. - Soulkeeper (talk) 11:14, 8 May 2011 (UTC)

Whichever way you look at it, this still isn't an example of genetic drift. It may be due to natural selection not to waste resources. "Regressive" refers to ill-defined measures of complexity, and is a whole other can of worms. By "directional", I mean "the direction can be predicted in advance with greater reliability than strictly random sampling odds", which applies to this case and rules out drift, even if the trait is neutral. As a professional theoretical population geneticist, I know that the term "drift" is problematic in many of its common uses. In an article aimed broadly, I think the best strategy is to say relatively little about such a subtle concept, but to make sure that what is said is 100% correct. I have tried to do some more detailed clarification on the genetic drift page, and will continue to do edit that one, but meantime still think this eg should be deleted from the evolution page.Joannamasel (talk) 18:18, 8 May 2011 (UTC) On second thoughts, I think a somewhat larger change is needed on this point. The article talks about only 2 mechanisms of evolution: selection and drift. But mutational bias is also a mechanism, mutation is not merely a source of variation for selection and drift to act upon. Not only does mutational bias it explain many instances of "regressive evolution" (the tendency for complex traits to be lost in the absence of selection), but it also must be invoked to explain phenomena such as GC content and resulting codon bias. Mutation bias also sometimes explains why one rather than a different solution evolves by natural selection. Acknowledging this requires some changes in multiple places in the article. Thoughts? Joannamasel (talk) 19:26, 8 May 2011 (UTC)

Perhaps you could present a draft that includes the changes that you have in mind? That way, folks can have a look and maybe do further edits if necessary? mezzaninelounge (talk) 19:30, 8 May 2011 (UTC)

I'm not very good on the technical side of wikipedia yet. How does one set up a draft, and then how does one reconcile that at the end with what might be conflicting edits in the meantime?Joannamasel (talk) 20:23, 8 May 2011 (UTC)

Do you want me to set up a page on your user talk? You can watch what I do, and repeat it elsewhere. OrangeMarlin ^{Talk• Contributions} 21:33, 8 May 2011 (UTC)

Danielkueh's edits helped in terms of what I thought was most immediately problematically in the article as a whole. Maybe I'll just write a draft copy of a new "mutation bias" section under mechanisms, rather than deal with systematic changes. I'll move the regressive evolution eg to there. But it probably won't happen for a few weeks.Joannamasel (talk) 14:51, 9 May 2011 (UTC)

if the article only covers selection and mutation than that is a gaping hole; recombination is by far the most important mechanism for asymptotic adaption / optimization. And recombination is definitely not drift, as it's a reductive process whereas drift implies an expansive process. Mutation (drift) simply prevents over-fitting / keeps the variety from getting too small, and it in fact is quite rare (on the order of 1 in a million codons). Kevin Baas^talk 17:07, 9 May 2011 (UTC)

If for the purpose of the "mechanisms" section, evolution is defined as a change in allele frequency over time, then selection, drift and mutation bias qualify, recombination does not. It stays under the variation section, but not also under mechanisms.128.196.198.191 (talk) 20:26, 9 May 2011 (UTC)

Joannamasel, take your time and thanks for the help. mezzaninelounge (talk) 21:07, 9 May 2011 (UTC)

Recombination has an exponential effect on allele frequency, whereas mutation's effect is only linear. That is one of the reasons that it becomes so dominant as a mechanism for adaptation. Kevin Baas^talk 12:24, 11 May 2011 (UTC)

I'm not sure mutation bias is really in the same boat as selection and drift, here. In this case you're talking about features (say, a gene) that are assiduously maintained by negative selection, and consequently they might have a stronger mutation pressure on them than the background level on the genome as a whole. It might be the case as Joanna suggests that, following their obsolescence, the loss of those genes is due to selection because they take up too many resources; or it might be due to high mutation pressure and those mutations simply drifting to fixation (this might have been the subject of research, and an interested party might want to chase this question down in the literature) - but in either case the mutation bias isn't producing the change. That mutation bias still exists when negative selection is maintaining those traits; it's only the absence of that selection that allows drift (or positive selection) to fix those mutations. Graft | talk 21:53, 9 May 2011 (UTC)

Organization of article

Mutation as a subject has been moved from Variation to Mechanisms. While I agree that mutation is one of the mechanisms of evolutionary change, I am not too sure that we need to move it from variation to mechanisms. The current layout gives the impression that mutation is not a source of variation. I prefer the original layout. Thoughts? mezzaninelounge (talk) 23:46, 25 May 2011 (UTC)

Mutation, itself, is not a mechanism of Evolution. In fact, I believe I've read the vast majority (far north of 90%) of mutations are deleterious. Genetic drift is it. If you don't revert the change, I will. OrangeMarlin ^{Talk• Contributions} 00:15, 26 May 2011 (UTC)

I'm moving it. Making that big of a change without discussion is odd at best. OrangeMarlin ^{Talk• Contributions} 00:19, 26 May 2011 (UTC)

The Mechanisms paragraph starts The four main mechanisms that produce evolution are mutation, natural selection, genetic drift, and gene flow. This makes this paragraph a natural choice for the Mutation paragraph. The problem is that the article tries to discuss Variation before discussing Mechanisms. I guess the cause of this is that Darwin started with variation, stuff that he knew about, while the modern approach is to view evolution as a process. In this perspective variation is a result of the process at work. This is what the article should show. --Ettrig (talk) 09:58, 26 May 2011 (UTC)

I suggest we go back to the original layout, whereby we have mutation as a description in the variation section and then a specific description of it as a process (mutation bias) under the mechanism section. This is consistent with most evolution textbooks and it is ok to have some duplicacy. See an example on Evolution 101, hosted by the University of California Berkeley [50] mezzaninelounge (talk) 12:10, 26 May 2011 (UTC)

The linked site describes mechanisms first and then variation (variation as a result (ultimately) of mutation). So should we. Good link! --Ettrig (talk) 12:29, 26 May 2011 (UTC)

I have no strong preference. I confess that I am use to Darwin's logic, i.e., describe variation first, and then the mechanism later. Either way, there has to be two separate descriptions. mezzaninelounge (talk) 12:35, 26 May 2011 (UTC)

I agree with putting it in twice, although I think the mutation bias section might need some re-working if it is going to serve as the description of mutation under the mechanism heading. Matthew Ackerman (talk) 13:50, 26 May 2011 (UTC)

So it is settled then, describing it twice. On a related topic, does anyone have a preference for the sequence? i.e., Variation, then mechanisms or Mechanisms, then variation. Just looking at the current textbooks out there (e.g., [51], it appears that the sequence of variation first, then mechanism later is quite common. I personally have no strong preference. I know Ettrig prefers listing mechanisms first, then variation. I just wonder what the rest thinks. mezzaninelounge (talk) 15:59, 26 May 2011 (UTC)

As I was about to restore the mutation text to its original location, I noticed that there is a short text under a subheading called population genetics in the Variation section. This text seems out of place as its main focus is not variation and its causes. Its main focus appears to be how Hardy-Weinberg equilibrium is used as a null hypothesis of evolutionary change within a population. This text should either be removed or moved to the mechanism section as a second paragraph (not necessary). Thoughts? mezzaninelounge (talk) 23:32, 26 May 2011 (UTC)

Hardy-Weinberg does seem out of place, as the absence of evolution. Does it need to be in this article at all? My vote would be to delete that paragraph, not that I have anything against the current paragraph per se, it's just not really about evolution. Also, for the ordering, I am not super-fussed, but knowledge has come a long way since Darwin and I don't think he automatically needs to be our guide here. I would vote either for mechanisms then variation, or for a super-brief variation summary, then mechanisms, then more detailed issues of variation like sex and recombination. I am not fond of the complex variation content then mechanisms.Joannamasel (talk) 01:12, 27 May 2011 (UTC)

Joanna, I agree that we should just delete that text. As for a super brief variation version of mutation, do you have a short text in mind? My suggestion would be to move paragraphs 3 and 4 to the variation section but keep the rest in the mechanisms section. Also, I think we should just remove much of the content in paragraphs 1 and 2. Much of that info is just overkill. It may be appropriate for an article on mutation but not so for an article on evolution. After that, we can switch the positions of the mechanisms and variation sections as you and Ettrig suggest. mezzaninelounge (talk) 01:52, 27 May 2011 (UTC)

I would just write something new for the superbrief version. Basically preface the mechanisms section and/or lead with the proviso that change in a population from one type to another can't happen unless variation between individuals exists, such that there is more than one type. And that mutation i.e. changes in DNA sequence during replication, are generally the original cause of this variation. I agree that much of the current mutation section is overkill and can be cut back. We should focus on what mutation means for a basic understanding of evolution. Oh, and one more thought on Hardy-Weinberg. I think it can go under variation just fine IF it is rewritten to focus on the contrast between blending and Mendelian inheritance, and why would be insufficient variation maintained under blending inheritance, a problem that Hardy-Weinberg solves. This is the historical role for H-W anyway.Joannamasel (talk) 03:14, 27 May 2011 (UTC)

Sounds good. Let's start with the text for the variation section. Have a look at the following proposed draft. It is a slightly altered version of the first paragraph of the original mutation text in the article. I am proposing this text for the variation section.

Random mutations constantly occur in the genomes of organisms, which produces genetic variation in a population. Mutations are changes in the DNA sequence of a cell's genome, which can be caused by radiation, viruses, transposons and mutagenic chemicals, as well as errors that occur during meiosis or DNA replication. When mutations occur, they can either have no effect, alter the product of a gene, or prevent the gene from functioning. Based on studies in the fly Drosophila melanogaster, it has been suggested that if a mutation changes a protein produced by a gene, this will probably be harmful, with about 70% of these mutations having damaging effects, and the remainder being either neutral or weakly beneficial.

I see what you're saying about keeping and modifying the Hardy-Weinberg text for historical reasons. Although I am not opposed to the idea, I do think keeping the text or a variant of it makes the article unnecessarily lengthy. This article as a whole could use some trimming. We've been talking for a while now on introducing new and important topics such as multilevel selection and cladogenesis, etc into this article but have yet to find much room for it. mezzaninelounge (talk) 04:32, 27 May 2011 (UTC)

I agree both with the text replacement suggestion and with the suggested removal of H-W. Joannas suggested rewrite can be added when someone comes around to write it. --Ettrig (talk) 07:06, 27 May 2011 (UTC)

I rewrote the H-W paragraph as I proposed, and no longer support deleting it right now, especially in the middle of a proposed/ongoing restructuring. Although I would be open to deleting it later as part of a largescale effort to reduce the total length of the article.Joannamasel (talk) 18:00, 30 May 2011 (UTC)

Arbitrary break for Mutations

Here is a suggested text for the "Mechanisms section": It is based on the existing mutation text.

A mutation is a change in the DNA sequence of a cell's genome. It can occur at different rates. There are three theories on what determines the mutation rate of organisms. The optimal mutation rate of organisms may be determined by a trade-off between costs of a high mutation rate, such as deleterious mutations, and the metabolic costs of maintaining systems to reduce the mutation rate, such as DNA repair enzymes. Additionally, higher mutation rates increase the rate of beneficial mutations, and evolution may prevent a lowering of the mutation rate in order to maintain optimal rates of adaptation. Finally, natural selection may fail to optimize the mutation rate because of the relatively minor benefits of lowering the mutation rate, and thus the observed mutation rate is the product of genetic drift. Viruses that use RNA as their genetic material have rapid mutation rates, which can be an advantage since these viruses will evolve constantly and rapidly, and thus evade the defensive responses of e.g. the human immune system.

Mutations can involve large sections of a chromosome becoming duplicated (usually by genetic recombination), which can introduce extra copies of a gene into a genome. Extra copies of genes are a major source of the raw material needed for new genes to evolve. This is important because most new genes evolve within gene families from pre-existing genes that share common ancestors. For example, the human eye uses four genes to make structures that sense light: three for colour vision and one for night vision; all four are descended from a single ancestral gene.

New genes can be created from an ancestral gene when a duplicate copy mutates and acquires a new function. This process is easier once a gene has been duplicated because it increases the redundancy of the system; one gene in the pair can acquire a new function while the other copy continues to perform its original function. Other types of mutations can even create entirely new genes from previously noncoding DNA.

The creation of new genes can also involve small parts of several genes being duplicated, with these fragments then recombining to form new combinations with new functions. When new genes are assembled from shuffling pre-existing parts, domains act as modules with simple independent functions, which can be mixed together creating new combinations with new and complex functions. For example, polyketide synthases are large enzymes that make antibiotics; they contain up to one hundred independent domains that each catalyze one step in the overall process, like a step in an assembly line.

Changes in chromosome number may involve even larger mutations, where segments of the DNA within chromosomes break and then rearrange. For example, two chromosomes in the Homo genus fused to produce human chromosome 2; this fusion did not occur in the lineage of the other apes, and they retain these separate chromosomes. In evolution, the most important role of such chromosomal rearrangements may be to accelerate the divergence of a population into new species by making populations less likely to interbreed, and thereby preserving genetic differences between these populations.

Mutation Bias

Mutation bias is the different probabilities at the molecular level for different mutations to occur. If two genotypes, for example one with the nucleotide G and another with the nucleotide A in the same position, have the same fitness, but mutation from G to A happens more often than mutation from A to G, then genotypes with A will tend to evolve. Mutation bias effects are superimposed on other processes. If selection would favor either one out of two mutations, but there is no extra advantage to having both, then the mutation that occurs the most frequently is the one that is most likely to become fixed in a population. Mutations leading to the loss of function of a gene are much more common than mutations creating a new, fully-functional gene. Most loss of function mutations are selected against. But when selection is weak, mutation bias towards loss of function can affect evolution. For example, pigments are no longer useful when animals live in the darkness of caves, and tend to be lost. This kind of loss of function can occur either because of mutation bias, or because the function had a cost, and once the benefit of the function disappeared, natural selection leads to the loss. Loss of sporulation ability in a bacterium during laboratory evolution appears to have been caused by mutation bias, rather than natural selection against the cost of maintaining sporulation ability. When there is no selection for loss of function, the speed at which loss evolves depends more on the mutation rate than it does on the effective population size, indicating that it is driven more by mutation bias than by genetic drift.

Thoughts? mezzaninelounge (talk) 15:11, 27 May 2011 (UTC)

My initial, first read, thought is that it still makes an implication that mutation is a mechanism. It's more clearly the mechanism of the mechanism (genetic drift). Mutations, being mostly non-beneficial, is really not a mechanism of evolution. OrangeMarlin ^{Talk• Contributions} 16:26, 27 May 2011 (UTC)

I see what you're saying and a part of me is inclined to agree. It appears that mutation as a mechanism appears to be restricted to the evolution of viruses. Hence, the importance of mutation rates. Nevertheless, I am not too sure if this applies to eukaryotic organisms (I personally doubt it). As you correctly pointed out, it is more of a "mechanism of the mechanism" when it comes to animals and plants. mezzaninelounge (talk) 17:01, 27 May 2011 (UTC)

Hopefully more people will respond. Maybe I'm over-analyzing "mutation", but I think, believe, opine that we may be conflating mutation with genetic drift, which may not be appropriate. OrangeMarlin ^{Talk• Contributions} 17:09, 27 May 2011 (UTC)

There has been some back and forth revisions of the evolution page. The main point of contention appears to be whether "mutation" is a mechanism or process of evolution. At first, I myself never thought of it as a mechanism of evolution but just a source of variation, by which mechanisms such as natural selection and genetic drift can act upon. Then, a comment by 117.224.23.194 caught my attention as well as recent edits and comments by Joanna on the subject. I then looked at other reputable sites on the subject such as evolution 101, which is hosted by the University of California, Berkeley. It describes mutation as a mechanism of evolution and a source of variation. I also looked for peer-reviewed articles on the subject [52][53] and found that much of the discussion of mutation as a mechanism is restricted to the evolution of molecules and viruses. Granted, this could be the result of the keywords that I used to search for the subject. I strongly encourage editors to read the following review article [54] on the effects of mutation on phenotypic evolution. I also looked to see if the term is used as such in evolutionary courses at the college level and found a couple of examples [55], [56]. Thus, it appears that mutation is described as a mechanism of evolution by the scientific community. I guess some of us (myself included) did not learn it that way. mezzaninelounge (talk) 18:43, 29 May 2011 (UTC)

A bit of time has passed. If there are no further queries or objections, I will attempt to restore mutation to both the variation and mechanisms sections once Memorial Day is over. 17:18, 30 May 2011 (UTC)

Scientifically, there is no question but that mutation is both a mechanism and a source of variation. At this point, there are plenty of refs backing this up. To explain the science here, there are at least two conditions necessary for mutation to be only a source of variation and not a mechanism. One is that all mutation rates are symmetric, i.e. A to a happens at the same rate as a to A. This is rarely true. The second condition is basically that all mutations that could possibly be adaptive happen at exactly the same rate, so that selection alone, not mutation rates, determine which of them become fixed. This condition is clearly never met.

There is a lot of confusion about the relationship between mutation and drift. Here the scientific community itself is guilty of frequently imprecise language that confuses the issue. But you will find that genetic drift is generally defined quite clearly today as sampling error. Fixation due to genetic drift is an unbiased lottery. Fixation due to mutation bias has one type more likely to become fixed than another BECAUSE OF MUTATION RATES. This makes mutation a mechanism that is distinct from genetic drift.

The real issue here is not to argue the dual role of mutation, but to figure out how to structure the article, with the 2 sets of questions of what needs to be split/duplicated, and which order sections should come in. Re splitting mutation, I think the best way to go is to start with mutation appearing twice, and then in continuing edits make sure that each point made is most appropriate in the section it is in, rather than the alternative mutation section.

That said, I think most of the first paragraph above, on the evolution of overall mutation rates (rather than the evolution of their biases) belongs under variation, not mechanisms. Ditto for the rest of it up to mutation bias, which basically describes what sort of mutations are possible, but does not discuss their relative rates. The mutation bias section is the only part of the above that I would put under mechanisms. Some of this material may be too indepth for the purpose of a general introduction to mutation. For example, most of the last paragraph before mutation bias might better belong under speciation. I am open about this one though.Joannamasel (talk) 17:58, 30 May 2011 (UTC)

Edit war

I am in an edit war with OrangeMarlin over two issues. Could the rest of you please weigh in on these?

First, some edits I made to the paragraph on Hardy-Weinberg. My view is firstly that these edits were necessary to make Hardy-Weinberg relevant to the evolution article in general and the variation in particular. The article is about evolution, not lack thereof. Second, I closely followed the historical material given in Ewens' monograph. OrangeMarlin has complained that these changes should have first been discussed on the talk page (which they in fact were, in the context of deleting the paragraph). OrangeMarlin also claimed that these changes constitute an original synthesis. I maintain that they closely follow Ewens text. Can someone please adjudicate this?

Second, since there was already a section on online lectures featuring one by Sean Carroll, I posted a link to a lecture of my own. This was a public lecture as part of a series hosted by the College of Science at the University of Arizona, with attendance of many hundreds of people, many turned away after the overflow room filled up. It received local press coverage. It was later broadcast on youtube and this is what I linked to. OrangeMarlin claimed that one cannot link to youtube, so I linked to a different recording of a similar lecture in the Maggie & Nick DeWolf Series in Aspen, available online through its broadcast on the local TV station. This also received local press coverage, including a TV interview.

I give these lectures quite often to explain the basics of evolution to the general public, and regularly give modified versions as part of K-12 teacher development on the topic of evolution. These lectures consistently receive rave reviews. I believe that the lecture makes a great and accessible introduction to evolution, and this is why I posted it. I originally posted the youtube version because it has a shorter introduction, and because youtube runs smoothly on most devices.

OrangeMarlin's complains that neither I nor the lecture are "notable". I do not see where in the rules it is required that I be a notable person, nor what the criteria are for the lecture itself to be notable, and hence allowable. OrangeMarlin has also referred to it as LINKSPAM. I have no financial interests to promote here. I do not charge a speaker fee when I give these lectures, which I view as part of the outreach component of my profession.

My understanding is that self-citations are not automatically improper when the editor is an expert. The criterion here is expert, which I think I easily fulfil, not notable. But that one should always defer to the consensus judgement of the community on a case by case basis, which I am happy to do. Could someone please also adjudicate this one? Either by clarifying the relevant rules, or by commenting on the relevance of the video itself (the latter only after watching it, please).Joannamasel (talk) 21:54, 30 May 2011 (UTC)

I agree that the edits on H-D equilibrium do not violate any known Wikipedia policy and is uncontroversial. If anything, I would prefer that the entire paragraph be deleted. Nevertheless, the recent edits are an improvement over the existing one, which is completely out of place in a section that focuses on variation. See discussion above.

As for the video, I personally have no problems against it (I did watch it). Although it does not technically violate any Wikipedia rules, I suspect there are editors who might feel uncomfortable with it only because it might be perceived as self-promotion or lacking notability/authority. I will leave this to the other editors. mezzaninelounge (talk) 22:11, 30 May 2011 (UTC)

I don't think the video adds much by way of extra information and it is self promotion.Teapotgeorge^Talk 22:16, 30 May 2011 (UTC)

Non-notable video placed purely for self-promotion by the non-notable lecturer. It's deleted. Fuck the world. As for the edits, again, we seem to rely upon opinion rather than anything else. The appropriate Wikipedia guideline is WP:BRD. The longstanding edits stay until there is a strong consensus for change. However, I do agree with deleting the whole thing. Joanna...you really need to review WP guidelines. But I actually don't give a shit if you do or not, purely your choice or not. OrangeMarlin ^{Talk• Contributions} 22:26, 30 May 2011 (UTC)

I have no personal opinion about the video. I do recall that WP's standards for formatting articles has changed a lot, but we used to make a distinction between works cited to support diferent propositions, and a section of recommended or related work interested readers could look at. I think this is a valuable distinction, and we generally have much looser standards for what goes into "for further reading" section than we do for reliable sources. As for mutation being a mechanism, I think we must follow the sources. If reliable sources represent the view that mutations can act as a mechanism of evolution, we should say so. Often times edit wars occur because edits do not povide appropriate context, and this may help here. If textbooks do not say that mutations are a mechanism and peer-reviewed articles only started referring to them as mechanisms recently, well, most of us should understand the reason for this. We just need to say so. But if this is a recent trend the distinction between majority/minority/fringe may not be the real issue here and may not help. We may have a view that is not technically fringe, but that is still emerging based on new trends in research and perhaps new technologies and we should explain so. My point is that we should have a way to present emerging trends in research which would not imply that the views are fringe, but that would be proportional, that would not give it undue weight. It sounds to me like an issue here is proporton: should mutation be given equal weight to mutation that it gives to natural selection or drift? Maybe not. Maybe what we should be working on is how to present an emerging trend in the literature that neither presents it as mainstream nor as fringe. Slrubenstein | Talk 22:47, 30 May 2011 (UTC)

Slrubenstein, I inserted a qualifier at the beginning of the proposed mutation text for the mechanisms section. Do have a look at both texts and let me know what you think about them. Thanks again for joining in the discussion here. mezzaninelounge (talk) 23:13, 30 May 2011 (UTC)

OK, I will not reinsert the video link. But I will restore my H-W edits. Neither in this thread nor the last has OrangeMarlin has defended his position that my text is a original synthesis / POV rather than an accurate summary of the Ewens ref. Meantime mezzaninelounge has described the edits as uncontroversial. I will also delete the legacy refs that I left in the text, in order to make it clearer which ref is being summarised by the text. As for the mutation as mechanism, it seems to me that consensus in favor is growing, and that the current text is inconsistent and must be changed one way or another, but I will leave others to make the call of when to move forward with that. Ditto for the ordering of variation and mechanisms, for which consensus seems less far advanced.Joannamasel (talk) 18:36, 31 May 2011 (UTC)

I strongly support the general edits of Joannamesel, and think it would be a grave error to oppose them. First, the organization of the article reflects the organization and pedagodgy of most introductory works on evolution. Freeman and Herron's first chapter in Part II of their book, entitled Mechanisms of Evolutionary change is Chapter 4: Mutations and genetic variation, and they open Part II with the following sentences: "Natural selection is not the only process that alters allele frequencies, however. There are three additional evolutionary forces: mutation, migration and genetic drift.", realizing that 'force' and 'mechanisms' are often used interchangeably.

Additionally, this formulation reflects the classic formulation in the field, going back the beginning of the modern synthesis. In his book The genetical theory of natural selection Fisher writes:

“A further hypothetical mechanism, guiding the evolution of the species according to the direction in which mutation are occuring, was suggested by Weisman.” and goes on to discuss the Weismann's somewhat incorrect ideas regarding biased mutation. However, he summarizes the kernal of this mechanism: “...Weismann's view that in the absence of all selection a useless organ might diminish, degenerate, and finally disappear, by the cumulative action of successive mutations, and especially his view that this is the only type of progressive change which could take place by mutations only, without the guidance of Natural Selection, is fully in accordance with modern knowledge of the nature of mutations.” Of course, Fisher goes on to reject the idea that biased mutation directs evolution to any appreciable extent; however, modern theorist do not, nor did all of Fisher's contemporaries.

Finally this leads me to a complaint about the proposed mutation as a mechanism edit: the edit begins with the word 'recently.' However, it was one of the core ideas of the modern synthesis that mutation could change allele frequencies (and hence, was a mechanisms of evolution). Therefore, if our goal is to reflect the traditional view of the field of evolutionary biologist, we must list mutation as a mechanism which is capable, in theory at least, of causing evolutionary change (again, defined as the change in allele frequencies.)

So, if Fisher calls mutation a mechanism of evolutionary change, we must call mutation a mechanism of evolutionary change. Matthew Ackerman (talk) 19:48, 31 May 2011 (UTC)

I agree that it's not, strictly speaking, a recent concept. Lynch 2007 cites Darwin and Muller among the "long been known". However, whether mutation bias is a significant vs insignificant force is a separate question from whether it is a force at all. The latter has long been known, the "recent" is really about the evidence of significance, as documented in the papers cited in the proposed text. At this point in the science, the evidence for the significance of mutation bias is stronger than that for genetic drift (if defined narrowly as sampling error). As for textbook approaches to organising coverage of evolution (rather than the content per se), that can sometimes evolve in its own partially-parallel pedagogical universe. Joannamasel (talk) 20:27, 31 May 2011 (UTC)

I'm on vacation so I haven't read all the dialogue but I will add my opinion. I find mutation a fact of DNA biology-not a mechanism of evolution (yes a mechanism of variation). We all know that cells possess mechanism to prevent such occurences but they still occur. Recent evidence in plants indicate that some mutations can be reversed-weird but a Science article with no apparent known mechanism. I would argue it as near-neutral molecular evolution. A mutation can occur and remain in a population cryptic for thousands of years and then natural selection act on the mutation to give it significance. Just as the transposon responsible for pesticide resistance in 80% of the worlds population of drosophila has been around thousands of years and only the last 200 years it has gained evolutionary significance. Mutations aren't random as genome seqencing reveals hotspots of mutation in various organisms, and the types of mutations are often restricted by Darwinian mechanisms as a Science article reflects in bacterial mutations and evolution. My opinion is mutations occur and the processes of evolution will determine whether it will ever have evolutionary significance. As far as Hardy-Weinberg, I know many evolutionary biologist seem to belittle HW, but it is a null hypothesis for evolution, and evolution must be testable and falsifiable. Science is a process-which I've been reminded so because of the recent study in humans with low salt diets being just as dangerous for stroke and cardiac arrest as high salt. I personally believe that gene flow as hydridization and HGT are a mechanism of evolution and there is a significant literature to support, but I wouldn't add it to this yet till the literature sorts it out. A good idea will mature and float so patience is a virtue. As I recollect Sewall Wright also argued Genetic drift can produce adaptions with his further theory (which evades my memory at present). But I doubt anyone would add this to the article because of Wright and Gould making such claims. Cheers GetAgrippa (talk) 20:55, 31 May 2011 (UTC)

I think there are two semantic/conceptual issues that will always plague this discussion. Unless a philosopher of science has addressed these, I would just go with the most common usage in academic publications by evolutionary scientists, rather than argue out these issues. But, one issue is (1) the word mechanism. Mechanics is a great term for physicists since they study the consistent efects of one force on one object. But by the time Darwin was writing physicits were abandoning Newtonian mechanics for statistical models of the universe and by the time the moden syntheis was developed, physicists were using "mechanics" only in very narrow senses. So maybe the word just is not the best word for evolution; maybe there are very few every-day words that are suitable metaphors for evolutionary biology (think of all the confusion lay-people have in the way they use such key words like "adapt," "fit" and "select," usually getting them completely wrong - some of this is due to their ignorance, some of it is due to evolution trying to explain things for which our language is an ineffective tool. (2) what comprises a complete description of the theory? Theories are meant to be reductive, they are not meant to describe everything, that would defeat the point. So no theory is self-contained, all theories assume certain things, which are essential for the theory to make sense but which are not formally part of the theory. So the question is, is this the case with "mutation?" Variation certainly was part of Darwin's theory, ven though he did not understand the mecahnisms of variation (e.g. mutation). Then again, I have always understood the modern synthesis to involve a synthesis of Gregor and Darwin i.e. incorporating the mechanisms of variation into the theory of evolution, so maybe now mutation is an essential part of the theory. Anyway, I suspect editors who disagree over Joannamasel's edits might really disagree over one of these two matters. Slrubenstein | Talk 12:05, 1 June 2011 (UTC)

Here's the count so far. We have 6 7 8 editors in favor of updating the current article, with 1 strongly opposed, and the other preferring a wait and see. Consensus? Yes? No? We have consensus. :) mezzaninelounge (talk) 13:01, 1 June 2011 (UTC)

Gene flow is missing from variation section

As I combed through this article again, I noticed that a description of gene flow is missing from the variation section but is listed as one of the sources of variation in the first paragraph of that section. Moreover, with the exception of the first sentence of the second paragraph under gene flow in the mechanisms section, that entire description of gene flow doesn't quite explain how it might function as a mechanism of evolution. It is just not clear. The reason why I brought this up is because there is a fast growing consensus to move the proposed mutation drafts to the variation and mechanisms sections, and I was wondering if we could also clean this bit up as well. I believe it might appropriate to move much of the current gene flow description from the mechanisms section to the variation section, and write a new description of gene flow that clearly explains how it may function as a mechanism of evolutionary change. Finally, I really think we should delete the description of population genetics from the variation section. It is completely out of place, even with the recent improved edits. mezzaninelounge (talk) 20:14, 31 May 2011 (UTC)

I'm happy with moving gene flow at least primarily to variation. Gene flow changes allele frequencies within demes, does not change overall allele frequencies within a metapopulation, but can change genotype frequencies. The main hypothesis of gene flow as evolutionary mechanism is Sewall Wright's shifting balance, which I just added one sentence on a short while ago. Wright's original model is discredited now, and it's a really difficult subject to summarise in an introductory article. Still, what I propose is that you move the majority of gene flow into the variation section, leaving a little stub in the mechanisms, and I will have a go at a _brief_ exposition of the concepts behind shifting balance. Joannamasel (talk) 20:39, 31 May 2011 (UTC)

Oh, but on further reflection, I oppose the complete deletion of population genetics, although I agree it needs a major rewrite. I think it is important to give the evolution = change in allele frequency definition somewhere, it is one of the leading definitions of evolution out there. And the new H-W content is both extremely important to the history of evolutionary thought, and a common so-called-evolutionary topic in introductory biology courses. Those are the two things I would like to leave in, I would be happy to see definitions of populations and gene pools go. I'm happy to try my hand at that rewrite too, but I would like the ordering of mechanisms vs variation to be sorted out first.Joannamasel (talk) 20:45, 31 May 2011 (UTC)

Fair enough. If we don't delete it, at least we should move the H-W model description to the first few paragraphs of the mechanism section. That way, readers would be able to see the connection between the assumptions of the H-W model and the mechanisms of evolution mezzaninelounge (talk) 23:05, 31 May 2011 (UTC)

Just a reminder: this article is very big. Over the years many spin-off articles have been created to avoid it getting even bigger. Whenever a subject starts becoming a major diversion we should consider that.--Andrew Lancaster (talk) 10:56, 1 June 2011 (UTC)

Andrew, that is a good point. I wonder if it would be better to just collapse all of the descriptions in each section into 2-3 paragraphs rather than having separate subsections like we do now. mezzaninelounge (talk) 13:47, 1 June 2011 (UTC)

I am not opposed to a substantial reduction in length, whether via spin-off articles or otherwise. However, I suspect the best way to get there from here is to get the content happy and well-structured in a longer version first with regard to the issues we have been discussing, and after this is done figure out which of all the content in the article it would be best to spin-off / summarise. Joannamasel (talk) 15:01, 1 June 2011 (UTC)

Maybe a good spinoff would be a page on "mechanisms of evolution". Slrubenstein is right, there is some intrinsic ambiguity to applying the word "mechanism" to evolution at all, let alone trying to produce a truly definitive lists. On evolutionary biology, we have the sentence "Evolutionary forces include natural selection, sexual selection, genetic drift, genetic draft, developmental constraints, mutation bias and biogeography": this another, non-contradictory way of slicing the same pie, which could be further elaborated on a spinoff page. Joannamasel (talk) 15:56, 1 June 2011 (UTC)

OK, let's wait a bit. So far it looks like the majority are in favor of the update. Give it a few days to the end of this week for any more discussion before making the updates. That way, at least we can be confident that the changes are long lasting and will not be subjected to back and forth reversions. mezzaninelounge (talk) 20:20, 1 June 2011 (UTC)

Help with Mechanism and Mutation in Evolution

The abstract in Ruse, M. (2005). Darwin and Mechanism: Metaphor in Science. Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences Volume 36, Issue 2, Pages 285-302 [57] - might help to clarify some issues about the mechanistic metaphor in evolution. Slrubenstein suggested that "mutation is one of the most important sources of variation, or of the dynamism of variation." There are other sources of variation, novelty, and innovation in evolution that do not rely on mutation that are just as important.[58] Environmental influences and other Eco-Evo-Devo factors. Here's my suggestion for the proposed section on Mutation Bias (I also drew and loaded an image showing transition vs. transversion nucleotide substitution):

The Ruse abstract is nice. But while the material in the other ref is fascinating stuff, I think it is a fringe view that this variation does not rely on variation. Much of the Lynch 2007 article is devoted to placing this claim in the fringe, so at minimum one can see that the view is disputed in the scientific literature. What Lynch and others do not dispute is a role for mutation bias, and they see these other phenomena as interesting examples of mutation bias / developmental bias / developmental constraints (the former term sometimes refers only to genotypes, the latter two explicitly to the phenotypic effects of mutations), including a possible dependence of mutation bias on the environment.Joannamasel (talk) 15:38, 2 June 2011 (UTC)

Mutation Bias Mutation bias is the different probabilities at the molecular level for different mutations to occur. If two genotypes, for example one with the nucleotide G and another with the nucleotide A in the same position, have the same fitness, but mutation from G to A happens more often than mutation from A to G, then genotypes with A will tend to evolve. If a mutation converts a purine (A or G) for a another purine or a pyrimidine (T or C) for another pyrimidine, these are called transitions. Transversions occur when purines switch for a pyrimidine or vice versa. If mutations were random there would be two times more transversional than transitional mutations. However, transitional changes occur more often than expected by random chance. The genetic code is also redundant with nucleotide subsitutions in third position of a codon having no effect or change of amino acid that is coded (synonymous mutations). Hence, the third position of a codon tends to mutate more commonly than the first or second position whose non-synonymous substitutions would change what amino acid was being coded for .

Transitional (Alpha) and transversional (Beta) mutations.

The problem with this change is that the new examples you give involve forward and reverse mutations with symmetric rates. While these new examples are also mutation biases, they are not a cause of evolutionary change. Unlike the previous example I gave, they have no effect on allele frequencies. So I oppose this change.Joannamasel (talk) 15:38, 2 June 2011 (UTC)

Incorrect. I score alleles on a daily basis and transversion to transition bias does have an effect on allele frequencies. I disagree with your comment that these nucleotide substitutions are not a cause of evolutionary change - they may not be a cause, but they are examples of evolutionary change on a genetic level. While I have no issue if my changes are accepted or not - the proposed paragraph was very poorly written and filled with errors.Thompsma (talk) 16:28, 2 June 2011 (UTC)

bias effects are superimposed on other processes. If selection would favor either one out of two mutations, but there is no extra advantage to having both, then the mutation that occurs the most frequently is the one that is most likely to become fixed in a population.[24][25] Mutations leading to the loss of function of a gene are much more common than mutations creating a new, fully-functional gene. Most loss of function mutations are selected against. Selection pressure, however, can vary greatly. Many cave dwelling species, for example, lose their eyesight and pigmentation. Under these circumstances, genes coding for pigments are and eyes tend to mutate more rapidly, because these traits no longer serve their original functional or adaptive utility in the darkness of caves.[26] There are alternative scenarios, however, where functional genes can mutate more rapidly than non-functional genes, such as under times of stress, in the immune-antigen system, or during sexual selection. (needs ref)

Why the deletion? And eyes do not mutate more rapidly in caves. The true technical meaning of random mutation is precisely that this does not occur, eg the Luria-Delbruck experiments. Mutation rates are independent of selection. What happens in caves is simply that there is no longer selection counteracting the everpresent mutation bias favoring loss of complex traits. I oppose this change.Joannamasel (talk) 15:42, 2 June 2011 (UTC)

I deleted because it was a convoluted steaming pile of wooji boogi statements that contribute little to the understanding of mutation bias. You are partially correct about genes coding for eyes in caves mutating more rapidly - there are examples where this has occurred:

• "According to the neutral mutation model, eye genes should be free to gradually accumulate mutations and eventually lose function if they do not have a critical role in other parts of the embryo or adult. However, downregulated genes involved in eye development have been difficult to identify in cavefish (Jeffery 2005). An exception is the aA-crystallin gene, which encodes an anti-apoptotic factor strongly downregulated in the lens of two different cavefish populations (Behrens et al. 1998; Strickler et al. 2007b)."[59]

There are other examples in cave dwelling insects where genes in eye development have increased rates of mutation (e.g., [60]. It was a simplified example and I thought I would bring in the example of the eye. The issue here is that you will always find exceptions - hence, we need more of a synthesis.

• The next part of the mutation bias:

This kind of loss of function can occur either because of mutation bias, or because the function had a cost, and once the benefit of the function disappeared, natural selection leads to the loss. Loss of sporulation ability in a bacterium during laboratory evolution appears to have been caused by mutation bias, rather than natural selection against the cost of maintaining sporulation ability.[27] When there is no selection for loss of function, the speed at which loss evolves depends more on the mutation rate than it does on the effective population size[28], indicating that it is driven more by mutation bias than by genetic drift.

• Can probably be removed. I don't like the either / or statement at the lead, like Gould[61] I'm always leery about ying / yang dualisms in science. I'm also slighly skeptical of the interpretation given from the primary literature that is cited. Someone posted a PNAS article written by Matsatoshi Nei earlier in this discussion.[62] Nei is a phylogenetic theoretician - mind and original author behind MEGA[63], and wrote some excellent books on evolution. On page 27 of Molecular Evolutionary Genetics[64] he has a figure on mutational bias that could help to simplify this section (which I re-illustrated above). The other problem with the existing text can be seen from this paragraph in Jablonka & Lamb's (2005) book[65] - which says something a little contrary to the proposed text on mutation:

"In general, DNA is more likely to change in regions where the chromatin is less condensed and genes are active than it is in more compact regions. That's because in active regions DNA is more accessible to chemical mutagens and to the enzymes involved in repair and recombination...For example, the base cytosine (C) mutates to thymine (T) more frequently when it is methylated than when it is not, and methylated DNA is usually associated with compact chromatin and inactive genes...DNA in the regions where genes are active is more likely to change than that in inactive domains."

Instead of deletion, I propose changing the "either/or" to an "and/or". There is no contradiction between Jablonka's text and the deleted text. Chromatin-driven mutation biases are certainly interesting, and I would support adding them to the text as an additional example, if related back to directional evolutionary change. But this has nothing to do with the loss-of-function bias deletion here, which I oppose.Joannamasel (talk) 15:49, 2 June 2011 (UTC)

It's just not written very well and it has errors. I would propose to start from scratch. I made the proposed changes late last night and quickly from the top of my head. The paragraph is all over the place. I would suggest building up from the single nucleotide substitution bias and then move into more complex examples. The bit about the mutation rate is wrong - once again, it is contextual - which is the basis behind Ohta's nearly neutral theory (see [66] & [67]).Thompsma (talk) 16:28, 2 June 2011 (UTC)

• The problem is that, yet again, that authors are getting trapped in a prescriptive view of evolution, when it is actually contextual and hierarchical. As Jablanka and Lamb (2005) state: "Lineages with DNA sequences that lead to a high mutation rate in the relevant genes survive better than those with less changeable sequences." This leads me to the notion of evolutionary burden - an evo-devo concept which Natsatoshi Nei touched on in the PNAS paper in another context. I'll use notochord for my example. Notochords are in us (humans) and in even tiny sea-squirt urochordates. Why is this morphological feature so conserved through evolutionary history? It is burdened - other adapted traits have evolved off the notochord (e.g., ribs, skulls, and other mesochymal derivatives, including pigmentation) and so it is burdened by these peripheral (autapomorphic) adaptations. Here is Nei's gene version:

This property appears to apply to many different animal phyla, and new species in each phylum are generated by mutational change of GRNs (Gene Regulatory Networks) in the final or near-final stages of development (94, 95). In fact, the evolution of eye spots in the wings of some butterflies or the evolutionary changes of the number and form of body segments in insects and vertebrates have occurred by modification of GRNs in late stages of development (43, 44, 96).

• Mutations occur more frequently in GRNs at the near-final stages of development - because the earlier stages are burdened by the later (introduced by Rupert Riedl - see [68]). Is there a way to integrate a hierarchical view of evolution? I really think it might help a lot of these debates - it puts things into context and it might help to stop the bickering.Thompsma (talk) 05:23, 2 June 2011 (UTC)

These are all really interesting points that I am very open to, but there are two issues. One is that for many of these topics, there is not yet scientific consensus. This isn't damning in itself, but especially in the context of a drive to make the evolution article shorter, I think this material would go better on more specialised pages. Suitable existing pages include mutation rate, evolutionary developmental biology, biological constraints and evolvability.Joannamasel (talk) 16:03, 2 June 2011 (UTC)

If you are going to wait for scientific consensus - you will be waiting a long time. I've seen that idea pop up in this discussion forum many times over - it is an absurd idea. That's not how science works - science thrives off dispute.Thompsma (talk) 16:31, 2 June 2011 (UTC)

Thanks Thompsma for the suggestion. I personally have no problems with it. As long as it is understandable (to anyone with just a high school education), not too wordy, and we can get a consensus to make the updates, then we should be good. You and Joanna should discuss this more (work out the details) as you two are probably most familiar with the literature on this. I'll just be the lazy editor and help with the insertion and deletion of texts. :) mezzaninelounge (talk) 15:22, 2 June 2011 (UTC)

P.S. Any suggestion for writing a quick text on how gene flow functions as a mechanism of evolution? We're trying to fix that as well. Nice diagram by the way, what program did you use? mezzaninelounge (talk) 15:22, 2 June 2011 (UTC)

I have some ideas...I will take some time to think this through a little more. I used Artweaver[69] - a free raster graphics editor.Thompsma (talk) 16:28, 2 June 2011 (UTC)

First off, I'm not dead set against the inclusion of text like this; however, I'm general think we should concentrate on the most essential ideas. For instance, I don't think it is necessary to discuss the mechanism of mutation bias (how many people really want to read about 8oxyG on this page?) etcetera. On the topic of canalization and developmental constraints etcetera, I could be convinced they are important enough to include (for instance, I think they are more important than the few sentences that we have on mutation rate equilibrium), but I haven't read over the article in good thorough way to see where they should be included. So, in short, I don't think this is appropriate for the mutation or mutation bias section, but could be added to other parts of the article; but more discussion is necessary. Matthew Ackerman (talk) 17:59, 2 June 2011 (UTC)

I agree with you Matthew Ackerman - looking at the article the section on mutation bias sticks out like a sore thumb. I jumped in here because I read the proposed paragraph and rolled my eyes, because it didn't make sense. I tried to edit it, but now standing back and looking at the whole article I don't understand why this has been inserted? It seems to me that this is a little project that someone is interested in, but it doesn't fit or isn't integrated very well into the whole article. This classical paper[70] published in 1945 in Science outlines the principals of integrative levels in biology and how I think this article could be better organized. This could serve as the bridge between the Dawkin vs. Gould camp - if you want an oversimplification of the diverse viewpoints. Once again - and I've made this complaint many times over in here - the emphasis is always on the evolution of genes. This is very unfortunate - because you cannot gather an emergent synthesis of the discipline without a hierarchical context. So long as the editors of this article continue to pick their little favorite article on genes and mutations the bickering in here will be a never ending story. I realize this is an ecology textbook[71], but I think that Figure 1-3 illustrates how the levels of biological organization could be integrated into this article on evolution. This is also the approach that was taken by Dr. Brian Hall in his textbook on evolution[72]. This way the discussion can be parsed and more easily argued in a logically consistent manner.Thompsma (talk) 22:26, 2 June 2011 (UTC)

Just to clarify, I think it is unnecessary to discuss the molecular mechanisms that causes mutations to be biased in a molecular context, not that it is unnecessary to talk about the fact that the phenotypic effects of mutations generally are biased. Some very general argument about how there are more ways to break a gene then there are ways to make a gene may be appropriate, I just think we should keep out explanations that might help clarify the concept to high level students, but would have little pedagogical utility to lower level students.

On the concept of levels of selection, etc., even though I am a population geneticist working in the Lynch lab, I think it would be entirely appropriate to discuss them. Besides, there are plenty of experimental evolution projects at this point that could provide enough support for an interesting hierarchical section. Matthew Ackerman (talk) 13:18, 3 June 2011 (UTC)

There is both continuity and discontinuity in the evolution of the universe; and consideration of one to the exclusion of the other acts to retard the development of biological and sociological sciences.

[73]Thompsma (talk) 01:06, 3 June 2011 (UTC)

I find it odd the rally to suddenly embrace mutationism, yet still the resistance to a heirarchial view and the influence of epigenetics (which I too suggested some 4-5 years ago). The literature has just grown in support of these ideas. Why don't we just take a NPOV and present the ideas, then give a consensus paragraph which reflects present thought. I was once told in this article that papers less than 5 years old were too new-well that time has elapsed. Thompsma suggestions embrace a "big picture" view which we should all embrace. Mutations within coding sequence, within regulatory elements, and epimutations all are viable. I think we need a double blind approach as we all have bias. Regards GetAgrippa (talk) 10:11, 3 June 2011 (UTC)

I second that. May as well just go all the way. mezzaninelounge (talk) 12:40, 3 June 2011 (UTC)

Beyond epigenetics - this article lacks many of the great evolutionary discoveries that could simplify things for a general audience. Homology is mentioned twice - no mention of Richard Owen in the history section. There is no mention of allometry, heterochrony, ontogeny, and there are four occurrences of the word morphology toward the end that reads more like an afterthought. No mention of ring species either - yet endless pedantic run on sentences filled with mistakes about genetic evolution. Developmental biology is given scant attention - despite its obvious prominence in evolutionary biology. I too have a history in genetics - my thesis was in phylogeography and I still work in a genetics lab since 2004. However, I would think that the article would be improved by starting off in more simple terms using morphology - which is at a level that high school students can grasp and it is also at the level that Darwin worked to originally develop the idea. There are fascinating examples of evolution at a morphological scale - from the adhesive pads of geckos to the scaling of sauropod dinosaurs - the mechanics of life is evolution in action. Yet everyone is focused on the abstract molecular scale where much confusion exists. I wrote the ecology article and placed the history section toward the end - a suggestion for this article as well. The more I look at this article - the more I dislike it. I think it gives a terrible overview of evolution in contrast to the rich history of evolutionary thought. It is surprising that I wrote the ecology article without a single controversy - yet this article is plagued by everyone bickering little points of no significance to the overall picture of evolution.Thompsma (talk) 17:19, 3 June 2011 (UTC)

Thompsa, hopefully we can streamline this through the use of a spinoff article on "mechanisms of evolution", once consensus is reached. Consensus now is still helpful in figuring out what the main evolution article will eventually just be summarising. I agree that many readers relate more to morphology than genetics. But nor can we leave the genetics out altogether, given its complete centrality to the professional science, encapsulated in the modern synthesis. Joannamasel (talk) 17:47, 3 June 2011 (UTC)

Of course genetics should be included - the point is that the layout and flow of this article is terrible and it is terrible skewed toward a very narrow genetical view of evolution. It is completely off the mark. Almost no mention of paleontology and phylogenetics is mentioned twice - never explained. Systematics is mentioned once in the lead - nowhere else and never defined. George Gaylord Simpson seems to be an important figure in evolution - no mention of him Tempo and Mode in Evolution was a groundbreaking book in evolution! Only a single mention of Ernst Mayr I count 180 references to genes or genetics!!! Is this an article about evolution or is it an article about genetics? I'm a huge fan of genetics - Sewell Wright, John Avise, Matsatoshi Nei, Alan Templeton, Joseph Felsenstein, Daniel Hartl, Montgomery Slatkin, and even Motoo Kimura are some of my biggest geneticist heroes. I love reading about population genetics, phylogenetics, and the neutral theory of molecular evolution. Coalescence theory is a fascinating pastime. However, I'm certain that even these hard core geneticists would agree that for a general article on evolution this has gone way too far into trying to explain the micro-mechanics of genetic evolution. It is doing a great disservice to such a wonderful idea that evolution is. I've worked in paleontology labs and I can say that some of the most exciting work in evolution is taking place at the morphological level, but you wouldn't have a clue that this is taking place by coming here. I have had a 20 year subscription to the journal evolution and read each issue that comes across my desk - every issue has articles about something other than genes. The most recent issue has 25 articles - three focus on genetics, the others are about group selection, population level phenomena, fitness landscapes, growth, sexual selection, aposematic traits, reproduction, ontogeny, paternity, metapopulations, migration, dispersal, morphometrics, behaviour, and mating. How did this article get so skewed in comparison? Let's start to write about evolution - this is what the article is supposed to be about.Thompsma (talk) 18:56, 3 June 2011 (UTC)

I don't mean to apply pressure, but can we please finish off the mutation as mechanism description first. Once we have that done, then I think we should take GetAGrippa's suggestion and start revising and updating this entire article from top to bottom by including many of the ideas/fields in evolution that Thompsma has mentioned. mezzaninelounge (talk) 19:03, 3 June 2011 (UTC)

Again, I haven't really read the article from start to finish to make sure that all the cool things that should be included are, but I think it may be appropriate to have a high level discussion of what should be included in the article. There is also an introduction to evolution article that needs to be considered, so that we can make sure that they complement each other. Over the weekend I will work on writing up an outline of what the purpose and content of these articles are. [[Special:Contributions/68.76.210.70|68.7

I wrote this in wrong section below so I add here. I think Thompsma is right on center about morphology. Phenotype is exactly what Mendel and Darwin were addressing, and much of the early advances (to the present)are morpological. I remember how logical and obvious evolution became from taking comparative anatomy decades ago, then evo-devo logically follows course extending the same ideas to development. The three-spine stickle back fish supermodel examines phenotypes, genetcs, organismic interactions, and environmental influences. None by themselves is explanatory but all together tell a story. I think this is key to Thompsma's suggestions. I always liked Gould's notion of a bauplan. We need a bauplan to glue everything together. GetAgrippa (talk) 23:12, 3 June 2011 (UTC)