Talk:Evolution/Archive 37
This is an archive of past discussions about Evolution. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
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Manual archive, to get caught up?
This Talk page is 392 kb, which would have been considered ridiculously huge some time back. I see that MiszaBot is set to archive topics older than 14 days. That sounds rather utopian. How about reducing it to 7 days? And what if I do a one-time manual archive to get it down to 80 kb or so? EdJohnston 04:08, 16 April 2007 (UTC)
- Good idea, thanks. 14 days seemed to be working until recently. Gnixon 23:43, 16 April 2007 (UTC)
- OK, I did the manual archive, and this page is now down to a slim, trim 163 kb. Unfortunately, to see the beginnings of some current conversations you might have to refer back to Talk:Evolution/Archive 35. The expiry time on MiszaBot is now down to 7 days so perhaps MiszaBot will be able to keep up better than before. EdJohnston 02:09, 17 April 2007 (UTC)
The New Edit: Still Needs A Lot Of Work
I've been looking at the new edit... I appreciate the hard work that Gnixon and Silence have put into this, but unfortunately it doesn't yet seem like we've achieved the structure we've been working toward. First: If you want the article to be about EVOLUTION, then the pattern ("observations") to lay out in the beginning shouldn't be a whole half of the entire article's length, including sections of mixed pattern and process (and relevancy!) such as heredity, recombination, etc. I have a *huge* problem with the fact that the mechanisms of selection and drift aren't even arrived at until about halfway through the article! Beginning the article with "observations" doesn't mean clump all the rest of the biology at the beginning and move selection and drift that far down. I agree with the general structure of observations/mechanisms/history of life, but the article (as it stands) is crowded with all kinds of information at the front, taking up half the article before the most important things for Evolution are even mentioned. If you want to start out with Observations, start out with a short-ish section on the kinds of things Darwin and others observed that led to formation of the field -- then get into mechanisms right away, which is where a lot of the information currently in the top sections really belongs. I'm going to take a bold'ish crack at this, attempting to be completely in line with the discussions we've had... TxMCJ 09:17, 16 April 2007 (UTC)
- OK, I made a pass through the article, but ended up only making some factual edits here and there, and improving a few small things (including a few little things in the lead, nothing major). Now I'm sleepy and won't attempt a reorganization now. But specifically, in terms of this edit, I think the following changes would help:
1.) Take out the Heredity section, or trim substantially and integrate into Variation. Now, more than ever, it seems out of place and interrupting the flow of the rest of the article. Maybe even take out the recombination section... if nothing else, consolidate consolidate!
2.) Insert a brief section (not called "observations", but including those things) immediately after "History of Evolutionary Thought", so the reader is immediately given the short list of the kinds of patterns that Evolutionary Biology describes. This is what we agreed upon -- not really the article as it stands.
3.) "Basic Mechanisms" need to move up. Why? Because we didn't *at all* agree on expounding widely on heredity and variation before getting to mechanisms for the first time. Most of the material in the Variation section are in fact matters of process (mechanisms).
4.) I argue for putting Selection before Drift, because a.) Gnixon's argument to do the opposite makes no sense, b.) Selection is almost always much stronger than drift, c.) Darwin spoke of selection, never of drift, d.) selection has always held higher status in Evolutionary thought than drift, and is always taught first -- Probably because Darwin outlined it long before population genetics were worked out.
I'll have lots more, but it's bedtime... Keep it up folks TxMCJ 10:46, 16 April 2007 (UTC)
- The basic idea of the article's current layout is to first introduce variation and account for its source, then to explain the behavior of that variation under evolutionary mechanisms. Doing the reverse would leave the first sections ungrounded: we'd be discussing genetic drift before we've even explained what a gene is! However, I fully appreciate your concerns, and my attempt to find a middle ground between the problem of leaving the basic mechanisms until too late in the article, and the problem of leaving terms undefined and concepts unexplained that are essential for understanding what selection and drift are operating on, has been to try to present the basic accounts of selection and drift, in summarized form, at the very beginning of the article: you'll notice that almost half of the lead section has been devoted to explaining these mechanisms, and you'll also notice that the very beginning of Evolution#Variation (which was formerly the first section in the article immediately after the lead) takes the time to explain drift and selection too. I think this (combined with some more work on compressing the "variation" section) is sufficient to make up for the problem of selection and drift being "too far down"; further, I think it's hard to argue that any major section in this article is non-essential, and I could see similar arguments being made for having the "common descent" section moved up based on its importance; ultimately we need to lay out the article in a way that lends itself best to reader comprehension, not in a way that moves from most to least "important".
- Silence, I appreciate your input and I agree with you on all of this. I agree that understanding heredity and variation are key (first principles) to understanding Evolution. Mainly I just think the article currently presents too much detailed information about *process/mechanisms* of Heredtiy and Variation, and more than is needed to get to the article's main theme: evolution and its mechanisms. After all, we could also insert a section on DNA structure and chemistry near the top, and a primer of population genetics, and a career biography of Charles Darwin and all the others. I'm being a bit silly, but my point is you have to draw the line somewhere, and get to the main themes of the article a lot sooner than we do in the current version. I agree 100% that we need to lay down core concepts first (like "what is a gene" (as you say), etc.) but I just think the current level of detail we are giving in those sections, before we ever get to the evolutionary mechanisms, is a little excessive at this point and detracts from the main themes. Readers can always link out of the Heredity and Variation sections (especially on things like recombination, HGT, etc.) if they want to. I'm not saying delete all that material, I'm just saying I think it ought to distilled down very, very much into the BARE MINIMUM that is needed to understand Evolution (because this article is about evolution), and then, present evolutionary mechnisms. More detail can be added later on or followed via links. Also, I like what you say about moving "common descent" up, and would agree with such a change as well -- mainly because, as I maintain, the article is really one about evolution and not all the basic biology we present. That biology is needed to understand the rest, but it just seems like the article requires you to climb over a bit too much outside information before you really get to the main theme of what the article is about. Thanks for sticking with this, Silence, an your input is some of the best I've seen around here. TxMCJ 17:53, 16 April 2007 (UTC)
- As for the "Observations->Explanations" layout idea, I've always considered this to primarily be of relevance to how text is organized within sections, not to how sections themselves should be organized (although admittedly it plays a role in that too at times); the article should primarily be of the format "Present facts A and B, then explain them; present fact C, then explain it; present facts D, E, and F, then explain them", not of the format "Present facts A, B, C, D, E, F, then present all the explanations for them". The purpose of putting Variation and Heredity before Basic mechanisms is to ground our readers in what evolution is acting on before we dive into precisely how it acts, so that the mechanism sections are clearly concrete, relevant explanations rather than empty abstractions; it is not to barrage them with trivial factoids before we even begin to address explanations. -Silence 17:08, 16 April 2007 (UTC)
- I think the "Heredity" section, incidentally, would be a good candidate for including the proposed "list of observations" you think we should have, if only because of its broadness: anything dealing with the inheritance of traits or genes, which should surely be the main class of phenomena which evolutionary theory explains, can be discussed there. It already serves that function to some extent, what with explaining Mendel's observations and how they were accounted for and explained. We can just take out some of the trivia (the last two paragraphs can probably be cut or significantly shortened) and replace it with more phenomena to be subsequently explained.
- As for the argument that selection is stronger than drift, I'd say that that's exactly why we should discuss drift first: begin with the "baseline" effect that's present even at the smallest levels, and then explain the exception. Doing the reverse, again, leaves people ungrounded, since we won't even have established the random sampling of traits before discussing their nonrandom selection.
- Interesting idea... let me think about that :) TxMCJ 17:53, 16 April 2007 (UTC)
As for the Darwin argument, this is an article on modern evolutionary theory, not on Darwin or on his original writings or theory. Darwin is only important insofar as he helps us to explain evolution; we owe him no debt. This isn't even a historical article, though history can be a useful tool for grounding concepts. I think you're thinking about this the wrong way, in arguing that we should present sections in an order based on which has "higher status" or is "stronger"; our purpose is to explain all important facts about evolution in whichever way most benefits the explanation of everything important, not to explain some important evolutionary topics (e.g., the ones Darwin discussed) and mention the others only as an afterthought. That will lead to a stilted, inconsistent article, rather than a cohesive whole in which the sections feed into each other and contribute to a cumulatively greater understanding. -Silence 17:19, 16 April 2007 (UTC)
- I hear what you're saying. However, I am not really arguing on an order based on "status" or "stronger". Modern evolutionary thought really exploded with the publication of the Origin, and while we owe "no debt" to Darwin (although he was the most significant contributor), the whole history of the field has been initiated and guided by the writings in the Origin. Doesn't give them "higher status", but it does make them more fundamental, in a way. Anyway, I am not arguing strongly for "ranking" topics based on importance, so there's not a whole lot of need to stress about this... Thanks & cheers, TxMCJ 17:53, 16 April 2007 (UTC)
- The prominence of natural selection makes it more "fundamental" in the sense of being more widely-known and associated with evolution, but it doesn't make it more "fundamental" in the sense of being the very first thing that needs explaining. It sounds like we mostly agree on this issue. -Silence 04:08, 17 April 2007 (UTC)
Separated Selection and Adaptation
Not sure if these two topics were always clumped together, but whether they were or weren't: they shouldn't be. I have separated them into two sections, added a bit more on Adaptation to flesh it out, and provided separate details links (the previous one that said "for more information about Natural Selection, please see Adaptation" was probably an oversight. I hope so anyway!) TxMCJ 23:04, 16 April 2007 (UTC)
- I'm very glad for drawing the clearer distinction between adaptation and selection, as the article formerly blurred the line between the two and thus left both terms ambiguous. However, I'm wondering if we might make Adaptation a subsection of Natural selection, since they're so clearly related, and since I'm not sure that "Adaptation" is really a basic mechanism in the same sense that selection and drift are?
- My response to that, is whereas it's true that adaptations arise as a result of the mechanism of selection... so does every other observable aspect of an organism. Why to give special preference to place "adaptation" under selection, and not place other organismal qualities under selection, is not immediately clear to me. TxMCJ 19:40, 17 April 2007 (UTC)
And two more points, if you don't mind: 1.) An adaptation (a noun that nowadays tends to refer to the TRAIT more so than the PROCESS) is really nothing more than a trait that can be demonstrated to have evolved under selection pressure to enhance performance of some function. It is not a "form" or "subcategory" of selection any more than an "evolutionary trade-off", a "vestigial structure", "or "junk DNA" is a form or subcategory of selection. Some early writers used to use "adaptation" synonymously with "selection", but a more formal definition defines adaptation as the TRAIT, and places strong emphasis on historical function vs. current utility.
My second comment is that natural selection *is not dominated by nor characterized as* "mainly" adaptation -- although the notion that selection equals adaptation is a very common misconception. Gould and Lewontin's paper on the Spandrels of San Marco/Panglossian Paradigm/Adaptionist Programme, is the classic paper on this subject. A modern article about Evolution really shouldn't mix selection and adaptation together as if they're somehow the same thing, and as if selection tends to be "adaptive" (again: because specific traits and functions need to be linked throughout time). Thanks for listening, TxMCJ 06:08, 17 April 2007 (UTC)
- The purpose of subcategorizing adaptation under selection wouldn't be to emphasize that selection is always adaptive, but rather to emphasize that adaptation is fundamentally selective in a way more dramatic and obvious than any other topic currently covered in the article is. You yourself weren't able to define adaptation without appealing to selection both times, something that's not the case for any other topic we've devoted a section to on Evolution. Regardless of where we end up putting the section, though, I recommend expanding its scope a bit: "Adaptation and exaptation", at the very least.
- You're right, it's hard to talk about adaptation without talking about selection. But it's hard to talk about a lot of evolutionary topics without talking about selection. Anyway, as long as the conceptual and factual distinctions are made, I suppose I don't care a whole lot about what the section heading is. TxMCJ 19:42, 17 April 2007 (UTC)
- Incidentally, subcategorizing it under selection, I think, would make it all the easier for us to clearly note in the section that, although selection is crucial for adaptation, the two are not one and the same. I don't think this sort of subsectioning would introduce ambiguity of the sort you're afraid of; in particular, because we'll have another subsection in the same place, "Competition and cooperation" (which clearly isn't trying to equate itself with natural selection either, merely pointing out the close relationship), I don't think readers will leap to such strange conclusions merely from an organizational issue like this. -Silence 16:17, 17 April 2007 (UTC)
- I'm also going to restore the "Competition and cooperation" section unless someone explains why Evolution shouldn't cover this important topic (if only to help clear up the common misconception that evolution is purely about "nature, red in tooth and claw" and all-against-all survival of the fittest, and the consequential misunderstanding that things like love and altruism and companionship are in any way anti-evolutionary).
- I'm also, of course, going to restore the vitally important section on "Modern research". -Silence 04:08, 17 April 2007 (UTC)
- Digression: vandalism to that article has drawn to my attention Survival of the fittest#Kropotkin and "survival of the fittest" – survival of the co-op! .. :) .. dave souza, talk 08:17, 17 April 2007 (UTC)
- Good ideas. FOR and FOR (sight unseen, of course... may have comments once they're back up) TxMCJ 06:09, 17 April 2007 (UTC)
I agree completely with MCJ's point about adaptation refering to a train and not a process - and I think the article needs to explain this very clearly, and be consistent in its use of language so as not to mix-up readers on this point. Slrubenstein | Talk 11:25, 17 April 2007 (UTC)
- I agree as well. I think this can be addressed by simply noting it in the section in question (much like speciation notes the misconceptions involved in "men evolved from monkeys, so why are there monkeys?"); my recommendation above about where to place "adaptation" was about layout, not content. -Silence 16:17, 17 April 2007 (UTC)
Comments on recent changes
"Heritable" was the term used in the lead for a very long name; it was changed to "inherited" purely for the sake of trying to avoid throwing any remotely opaque terminology at readers so early in the article. Most editors seemed to agree that "inherited" was an adequate replacement, and that it was much more accessible to new readers and thus a much better term for the purpose of drawing readers into the article. Is there any compelling reason why inherited is unacceptable?
- I tend to use "heritable" more, because "heritable" is a strictly descriptive adjective while "inherited" is a verb-adjective and for that reason, not as informative about the property of heritability. I think the use of "heritable" is also a good habit to get into, to immediately distinguish heritable traits from acquired ones. Dig this: coming flat out and saying "a heritable trait" immediately excludes the non-heritable ones (i.e. acquired traits), whereas saying "inherited traits" merely excludes traits that were not inherited, whether they are heritable or not. Thus I feel there is more information conveyed by the word "heritable". Heritable is a QUALITATIVE adjective, while "inherited" is a CONDITIONAL/HISTORICAL one. Speaking of an "inherited trait" does not immediately or necessarily make any logical exclusion of non-HERTIABLE traits... it only excludes the non-INHERITED traits, thus leaving open the possibility that perhaps acquired traits are heritable. See what I mean? But I will agree to use inherited rather than heritable if people prefer... although there is an important yet subtle distinction, mainly tied to the exclusion of acquired traits. TxMCJ 06:40, 17 April 2007 (UTC)
- To aid those new to the term, how about changing the first mention to "Evolution occurs when differences which can be inherited become more common or more rare in a population", then wikilinking the following heritable (note it's a redirect to Heritability) for those still puzzled or wanting more info. ... dave souza, talk 08:34, 17 April 2007 (UTC)
- Your argument is well-made, TxMCJ, but I still feel that such a subtle distinction isn't worth the ambiguity the word will generate. Dave's suggestion seems reasonable. If it's really necessary to mention the word "heritable" in the lead section, we should at least avoid it in the very first sentence in order to make that sentence as clear and accessible as possible. (Alternatively, if others agree with avoiding the word in the lead section, introduce heritable in the "Heredity" section, then continue with it subsequently.) -Silence 16:37, 17 April 2007 (UTC)
- Allright, fine by me... I like Dave souza's advice about the "first mention", though. TxMCJ 19:44, 17 April 2007 (UTC)
- Your argument is well-made, TxMCJ, but I still feel that such a subtle distinction isn't worth the ambiguity the word will generate. Dave's suggestion seems reasonable. If it's really necessary to mention the word "heritable" in the lead section, we should at least avoid it in the very first sentence in order to make that sentence as clear and accessible as possible. (Alternatively, if others agree with avoiding the word in the lead section, introduce heritable in the "Heredity" section, then continue with it subsequently.) -Silence 16:37, 17 April 2007 (UTC)
- To aid those new to the term, how about changing the first mention to "Evolution occurs when differences which can be inherited become more common or more rare in a population", then wikilinking the following heritable (note it's a redirect to Heritability) for those still puzzled or wanting more info. ... dave souza, talk 08:34, 17 April 2007 (UTC)
- I tend to use "heritable" more, because "heritable" is a strictly descriptive adjective while "inherited" is a verb-adjective and for that reason, not as informative about the property of heritability. I think the use of "heritable" is also a good habit to get into, to immediately distinguish heritable traits from acquired ones. Dig this: coming flat out and saying "a heritable trait" immediately excludes the non-heritable ones (i.e. acquired traits), whereas saying "inherited traits" merely excludes traits that were not inherited, whether they are heritable or not. Thus I feel there is more information conveyed by the word "heritable". Heritable is a QUALITATIVE adjective, while "inherited" is a CONDITIONAL/HISTORICAL one. Speaking of an "inherited trait" does not immediately or necessarily make any logical exclusion of non-HERTIABLE traits... it only excludes the non-INHERITED traits, thus leaving open the possibility that perhaps acquired traits are heritable. See what I mean? But I will agree to use inherited rather than heritable if people prefer... although there is an important yet subtle distinction, mainly tied to the exclusion of acquired traits. TxMCJ 06:40, 17 April 2007 (UTC)
Why is "of a population or species" necessary? Aren't species just groups of populations, united by their ability to interbreed? Again, this is a major problem if our intent is to keep the first sentence(s) as concise and clear as possible.
- Because while populations evolve, so do whole species. Evolution can be characterized on both the population level and the species level. Also, the interbreeding criterion of species concepts only applies to sexually-reproducing organisms. Many organisms are asexual (yet still regarded as "species"), and thus population dynamics (and things like interbreeding) really play no role in asexual organisms. Also, I am continually troubled at how to present the idea of species in this article (and perhaps even the species article itself), since arriving at a useful definition of "species" that applies to all organisms has always eluded biologists. I'd like to get into that point here, but realize it will probably confuse most readers. TxMCJ 06:40, 17 April 2007 (UTC)
- The point about distinctions between "species" and "varieties" being elusive is is very important, and was emphasised by Darwin repeatedly – see below for a related suggestion. .. dave souza, talk 09:05, 17 April 2007 (UTC)
- Because while populations evolve, so do whole species. Evolution can be characterized on both the population level and the species level. Also, the interbreeding criterion of species concepts only applies to sexually-reproducing organisms. Many organisms are asexual (yet still regarded as "species"), and thus population dynamics (and things like interbreeding) really play no role in asexual organisms. Also, I am continually troubled at how to present the idea of species in this article (and perhaps even the species article itself), since arriving at a useful definition of "species" that applies to all organisms has always eluded biologists. I'd like to get into that point here, but realize it will probably confuse most readers. TxMCJ 06:40, 17 April 2007 (UTC)
- Absolutely... and "varieties" and "species" are still elusive (I mention some of this when talking about species, below.) Mainly I added "species" to the sentence, because evolution is not strictly changes within populations. Most of these little points we are debating stem from edits I made to be accurate, and while I won't argue for their necessary inclusion, some other solution will have to be implemented that makes all statements as accurate as possible. :-) TxMCJ 19:50, 17 April 2007 (UTC)
- And are the population and species levels the only levels at which evolution can be characterized? By concern with trying to be too all-encompassing with evolution's applicability is that (1) it makes the first sentence unnecessarily long, and (2) it leaves the door open to the insertion of trivial exceptions. Anything remotely trivial or non-essential should be saved for later in the article. However, with that in mind, if noting "population or species" improves clarity and accuracy, I don't have a big problem with it. I'm just encouraging caution with any expansion of the early article. -Silence 16:37, 17 April 2007 (UTC)
- I don't think there are other levels than populations or species to consider. Single individuals don't evolve, populations and species do, and while multispecies "communities" or relationships between species might evolve (e.g. via coevolution), that is sort of a higher level that is not immediately implied by "evolution". I dunno -- address this as you see fit. If you're OK with that edit, Silence, perhaps we'll just keep it, and all be cautious about unnecessary expansion... TxMCJ 19:50, 17 April 2007 (UTC)
Repeating "heritable" twice in a row, in one sentence after another, is just bad writing. "These traits" works perfectly fine, as there isn't any real ambiguity in context. (The third repetition, near the end of the paragraph, is also quite unnecessary. Nowhere in the lead section—or, indeed, in the entire article—do we discuss non-heritable traits, so it is quite misleading to repeat "heritable" so often, as it will imply to readers that we're discussing non-heritable traits every time we don't use the word "heritable"!
- All right. I have no issues with this opinion! Make the changes if you think it will improve the writing. Although some distinction of heritable vs. acquired traits must be made (if it's not there already, somewhere other than in the section about Lamarck). :-) TxMCJ 06:40, 17 April 2007 (UTC)
- How about if we devote a few sentences to clarifying that distinction at the very beginning of the "Heredity" section? Seems like the perfect place to explain the issue. -Silence 16:37, 17 April 2007 (UTC)
I like taking the time to note "differences (variations)"; I don't like throwing out undefined (and unnecessary) terms like alleles and independent assortment in the first paragraph. (You make the same mistake of using the term allele without bothering to 'n any way define or explain it at the start of "Variation". There's a very important reason why alleles were not mentioned until time could be given to sufficiently explain them.)
- The only reason I added alleles and independent assortment (with hyperlinks by the way, so readers COULD follow them...) was because in the previous version of this section, mutation seemed to be presented as the only source of variation. Mutation is not the only source of variation. If you leave mutation in there, you have to leave in mention of allele differences and independent assortment as additional sources of variation. If you want to talk about differences (variation) alone, then you will have to remove mutation, so we don't give the impression that mutation is the only source of variation. TxMCJ 06:40, 17 April 2007 (UTC)
- Hyperlinks don't justify leaving terms undefined; every Wikipedia article is expected and required to be able to function as a stand-alone article; visiting other articles should be purely supplementary, not essential for understanding the topic in question. This is especially important for the many planned print versions of Wikipedia, which evolution will almost certainly be included in. I think leaving in mutation while leaving out those other topics is fine as long as we are clear (and I think we are, or at least clear enough) in saying that mutation is an example of how variation is produced, not the only way it's produced. Hence "Mutations and other random changes in these genes". -Silence 16:37, 17 April 2007 (UTC)
- I sort of see your point, although technically, a mutation is an actual *change* in a gene, while differences due to alleles and assortment do not reflect actual *changes*, just aspects of variation itself. I just think we can do better than, "Mutations and other random changes". TxMCJ 19:53, 17 April 2007 (UTC)
Why drift before selection, at the end of the first paragraph? Isn't the original order a better way to transition smoothly into the second paragraph, which discusses selection, not drift?
- If you prefer. I just mainly thought it was better to mention selection first because of the Darwinian precedent, but either way I suppose is fine. TxMCJ 06:40, 17 April 2007 (UTC)
"As differences in and between populations accumulate, speciation may occur, resulting in the divergence of an ancestral species into two new ones." is an amazingly awkward sentence. Why not just "As differences in and between populations accumulate, species diverge and become separate species." or something?
- Hmm, well... Let me think how to make this less awkward. The previous version did not clarify that species is a bifurcating process where an ancestor splits into two descendants. It seemed more that it just said, "new species can appear", which is vague and can puzzle both creationists and biology students like. Also, a common misconception about speciation is that one of the daughter species is somehow the "original" species, while the other is the "new" one. Thus making a distinction between the ancestral species and the two descendant species is important if we want to get across that sister species have equal status with regard to the ancestor. Thus, "species diverge and become separate species" still seems a bit vague to me, and I think we can do better. How about: "As differences in and between populations accumulate, an ancestral species can diverge into two separate descendant species" -- or something like that. Please suggest some other wording or sentence structure that does not make it sound like species just "bud off" the existing lineage, and that makes a distinction between the ancestor and the descendants. Thanks, TxMCJ 06:40, 17 April 2007 (UTC)
- Sounds right to me. Adapting the existing phrase in the light of my comment about varieties above, how about something along the lines of "As differences in and between populations accumulate, distinct varieties can develop and when varieties are distinct enough to be described as a new species, speciation has occurred and so an ancestral species has diverged into two new ones." .... dave souza, talk 09:05, 17 April 2007 (UTC)
- Hmm, well... Let me think how to make this less awkward. The previous version did not clarify that species is a bifurcating process where an ancestor splits into two descendants. It seemed more that it just said, "new species can appear", which is vague and can puzzle both creationists and biology students like. Also, a common misconception about speciation is that one of the daughter species is somehow the "original" species, while the other is the "new" one. Thus making a distinction between the ancestral species and the two descendant species is important if we want to get across that sister species have equal status with regard to the ancestor. Thus, "species diverge and become separate species" still seems a bit vague to me, and I think we can do better. How about: "As differences in and between populations accumulate, an ancestral species can diverge into two separate descendant species" -- or something like that. Please suggest some other wording or sentence structure that does not make it sound like species just "bud off" the existing lineage, and that makes a distinction between the ancestor and the descendants. Thanks, TxMCJ 06:40, 17 April 2007 (UTC)
- How about just "species diverge into separate species"? I realize it's vague, but we can't explicate everything in the lead section, and I'm already a little concerned about whether we're excluding anagenetic speciations in favor of pure cladogenesis. Ah, here's another idea: rather than getting into "ancestor species" and "descendant species" (terms which, as you note above, have a bit of baggage that we'll need to explain away first), how about just "species diverge into separate new species"? Adding "new" will emphasize that neither one of the separated species is identical to the ancestor species. I don't like Dave Souza's version for the lead because it's too long and in-depth, though it might be useful somewhere ni the article body. -Silence 16:37, 17 April 2007 (UTC)
- Hmm, not bad, not bad. I think my caution here has to do with my wonder whether most readers understand "divergence" as a process that takes place over time, between ancestors and descendants. "Species diverge into separate species" just seems a little vague to me, but I won't harp on this. It would be a lot easier if we were talking about bread dough or something: "Bread dough is divided into two separate loaves". Obviously I am not arguing for inclusion of this metaphor, but it's a very good one because it parallels the fact that neither of the loaves is the "original" dough... or else, they both are. Anyway, edit as you see fit. TxMCJ 19:58, 17 April 2007 (UTC)
Mentioning the original Linnean Society presentation is absolutely unnecessary. It's hard to think of a more useless insertion for your average reader. If anything, we should be expanding and clarifying the lead's paragraphs on the evolutionary process, not on the theory's history! That's addressed just a couple of inches lower in the article's first section!
- All right -- my only reason for that edit was due to the pre-existing version of that section that made it out like Darwin's "The Origin" was the first presentation of evolution and natural selection, when in fact, the joint paper with Wallace preceded "The Origin" by several months (including a New Years' celebration!) I was just trying to be accurate -- remove mention in the lead if you'd like. TxMCJ 06:40, 17 April 2007 (UTC)
"In Darwin's day, the evidence of shared traits was based solely on visible observation of morphologic similarities, such as the fact that all birds, even those which do not fly, have wings." should absolutely be re-added to the article. Its removal is simply incredible. The point of this sentence was to contrast modern-day biology with Darwinian (and, by implication, pre-Darwinian) biology, clearly not to contrast Darwinian biology with pre-Darwinian biology!
- I only removed it because its meaning or purpose wasn't clear to me. In the future I will ask first, but I'm still not sure of the meaning or purpose of that sentence, and I think about this stuff every day, all day long. Is this merely a statement giving an example of homology? Or, if it is meant to contrast Darwinian/preDarwinian biology with modern biology, then what is the distinction between the two... the fact that we use molecular data today too as well as morphology, or something? Sorry for being so dense, but I really don't "get" this statement as written, or what point it is trying to communicate. Please explain, thanks. :-) TxMCJ 06:40, 17 April 2007 (UTC)
"through this process of gradual divergence" was completely and 100% correct; all evolution is gradual, as it occurs over the millennia of geologic time, not in sudden fits and starts. It is a common misconception that punctuated equilibrium is in some way not gradualistic, but in reality punctuated equilibrium is entirely gradualistic; it is only contrasted with phyletic gradualism, not with the very basic, universally-accepted idea that evolution is a gradual, rather than sudden (see saltation (biology) and catastrophism), process. -Silence 04:08, 17 April 2007 (UTC)
- OK. I won't argue against the fact that evolution takes *forever* (not literally), although divergence events certainly *do not* always require "millennia" (but I agree that most divergence events probably require at least several millennia)... but nonetheless, I think you may be right that the distinction between gradualism and punc. eq. is more appropriate when considering phylogeny (although I always teach these two concepts in the context of "evolutionary rates"...) Revert to "gradual" if you prefer, and I'll get back to you if it still bugs me. TxMCJ 06:40, 17 April 2007 (UTC)
- Yep. Just check out our gradualism article, which points out that punctuated equilibrium is entirely gradualistic. Moreover, all that really matters here is that we take the time to briefly explain to our readers (most of whom won't even know what "gradualism" is) that evolution is an extremely slow process, by human standards; fish don't suddenly turn into squirrels out of the blue. More subtle distinctions of evolutionary rates can be addressed later in the article, but for the lead "gradual" suffices. -Silence 16:37, 17 April 2007 (UTC)
BS alert
Wow, I started reading this article and the amount of BS is astouding. It's not designed to inform, simply to confuse the average reader into a blind belief in the evolution fantasy. Looking over the talk pages, all of your blind faith is pathetic. What is this "evolution doesn't need proof" attitude anyhow? Even the gravity article explains why gravity exists, and what evidence supports it's existance. None of the sections are coherent, because of what looks like an obvious attempt to mask the difference between microevolution and macroevolution. Adaptation CANNOT LEAD TO SPECIATION, mutation is the only process so far theorized that at least ON PAPER can lead to new species. However, the current article doesn't even attempt to be honest on this point. Additionlly, there is a lot of B.S. "fat" added into this article, totally off topic, that only serves to confuse the subject without explaining the core of "evolution" theory. I'm going to mark this article POV and unsupported until I can get some science together to replace the crap the "church of evolution" here have put together.
THIS IS NOT TROLLING, OBVIOUSLY THIS PAGE IS RUN BY FANATICS WHO DON'T TOLLERATE DESENTING OPINION, TYPICAL OF THE FANATIC EVOLUTION COMMUNITY. THIS WILL CONTINUE TO BE REPOSTED UNTIL THE FANATICISM STOPS. DAVID, JUST CONSTANTLY DELETING OPINIONS YOU DON'T LIKE ISN'T GOING TO CUT IT. --Fm.illuminatus 17:01, 17 April 2007 (UTC)
- Your concerns are already addressed at Talk:Evolution/FAQ. Please read the information there. Specifically, Wikipedia policy forbids us from inserting our own opinions into the article (be they pro- or anti-evolutionary) even if we're sure we're right; only reliable scientific sources are relevant here. If your can back up any of your claims with any peer-reviewed scientific publication of any sort, we can add it to the article; otherwise, even if you were correct (and, as it happens, you are mistaken), we couldn't do anything about it. Wikipedia is based on the principles of verifiability and no original research, not on the opinions of its editors. -Silence 17:07, 17 April 2007 (UTC)
- The evolution article does explain why evolution exists, and what evidence supports its existence (review the "homology" sections, for example). If there's something you think is missing, please be more specific; do you think there is insufficient evidence provided for genetic variation? For common descent? For natural selection? For the inheritance of traits? If you have actual constructive information, we can work together to improve the article; if, however, you are only interested in pushing an agenda, you'll find your time here fruitless.
- Regarding "proof", evolution is either proven or does not need proof, depending on one's definition of "proof"; the exact same holds true for gravity. See Talk:Evolution/FAQ#But isn't evolution unproven?. As for microevolution and macroevolution, the only real distinction between the two is one of time and scale. Small changes add up to large ones over billions of years; this is a principle not just of evolutionary biology, but all the sciences. Look at the diversity of dog breeds that have arisen in only a few thousand years; do you really think that that same diversification, extended over millions or billions of years, couldn't possibly result in, say, a species diverging into lions and tigers, or into sheep and goats, or into cows and buffalos, or into zebras and horses? -Silence 17:20, 17 April 2007 (UTC)
- Isn't there something about not feeding trolls. No one should even respond to this hysterical diatribe. Orangemarlin 17:23, 17 April 2007 (UTC)
I removed his furth BS. It just does not belong on this talk page, which is for the improvement of the article. See "Important notice" at the top of the page. Slrubenstein | Talk 17:35, 17 April 2007 (UTC)
- I just reverted his rants again. I've reported him for WP:3RR so he can cool his jets. His civility is suspect too. Orangemarlin 17:49, 17 April 2007 (UTC)
- Wowee wow wow (in the words of Christopher Walken)... I agree we shouldn't feed trolls, now partially based on my recent experience "feeding" another type of creature that is always hungry for more. Thanks for handling this. I'm sure it's not the first or the last time... OH, and Orangemarlin? A hearty welcome back. :-) TxMCJ 20:01, 17 April 2007 (UTC)
Peace
Jeez, I'm gone for one day and now this? Here's the Talk history, see around 17:30, 17 April. Here's the Article history, see around 17:40, 17 April.
TxMCJ has succeeded in chasing me away permanently, but I'd like to offer one last piece of advice: think hard about what's the most efficient response to the objections from creationists that pop up here so often. So long, and thanks for all the fish. Gnixon 19:56, 17 April 2007 (UTC)
extrapolation error and microevolution leading to macroevolution
Examples of extrapolation error
An extrapolation's reliability is indicated by its prediction confidence interval, which often diverges to impossible values. Extrapolating beyond that range can lead to misleading results.
For example, the death rate from a new disease may increase dramatically early on. If the graph of the death rate is then extrapolated linearly, it might appear that the entire human population will be dead from the disease in a short number of years. In reality, the death rate from a newly discovered disease may fall as the susceptible die off and the remainder alter their behavior to avoid contracting the disease. Those who remain may also have a natural immunity to the disease or an acquired immunity due to exposure. Medical treatments affecting the spread and death rate of the disease may be developed, as well. A simple linear extrapolation assumes that there is an infinite population, and if the trend is growing faster than the population it will predict that more will have died than have ever been alive.
Similarly, if the amount of water in a lake is decreasing over time, a linear extrapolation will predict that there will be a negative amount of water shortly after the water is gone. This is an absurd result which indicates that the extrapolation is being performed in the wrong domain.
Selection of an improper domain, such as an infinite domain when all possible values are finite, or a negative domain for nonnegative values, is the second most common extrapolation error after failure to include a prediction confidence interval. 68.109.234.155 (talk) 19:39, 17 April 2007 (UTC).
- And.....I'm missing the point? Orangemarlin 20:39, 17 April 2007 (UTC)
- Unless this posting is a total mistake, I think the implied point might be, "I am a creationist who will attempt to convince you in an indirect way that the scientific logic behind Evolutionary science is wrong, by posting an opaque but seemingly rational and scientific diatribe about the error of extrapolating things that are impossible". I could be wrong... (or is this obvious?) TxMCJ 20:49, 17 April 2007 (UTC)
- Well, perhaps you're extrapolating from an apparently infinite number of editors who use the term "macroevolution" to mean "I've read something in AiG so that proves evolution must be wrong" to assume that this is another example of the same old deluded argument from yet another one who's failed to read or comprehend the FAQ linked at the top of the page. But, of course, perhaps not. ... dave souza, talk 21:18, 17 April 2007 (UTC)
- I think this user was trying to convince me a few weeks ago that aliens encoded DNA with a secret message. SETI and DNAOrangemarlin 21:24, 17 April 2007 (UTC)
- Well, you know if panspermia is true and prokaryotes arrived here on meteorites, I suppose anything's possible... ;-) TxMCJ 23:47, 17 April 2007 (UTC)
- I think the point has been missed by the above commentors. Too complicated to explain in this format. 68.109.234.155 00:12, 18 April 2007 (UTC)
- Most of us were joking. TxMCJ 01:15, 18 April 2007 (UTC)
- The occurrence of macroevolution, as well as the overwhelming majority of its general effects and consequences, is not based on extrapolating from microevolution. Rather, it is based on observed instances of macroevolution (e.g., speciations) and on the traces of past macroevolution in the form of fossils and anatomical and morphological vestiges. Extrapolating from microevolution helps us explain how macroevolution works, but it's not the primary source of information about macroevolutionary rates and effects. -Silence 00:34, 18 April 2007 (UTC)
- There are observed instances? Traces of past macroevolution? Does not macroevolution imply that the organism cannot even artificially mate with its predecessor while a micro change would not have that effect? Seems like a big difference to me. 68.109.234.155 00:45, 18 April 2007 (UTC)
- Speciation occurs over long periods of time, usually when an ancestral species gets divided into geographically isolated populations. Given sufficient time, evolutionary mechanisms (selection and drift) will handle the rest. Sexually reproducing organisms don't mate with the predecessor because the predecessor is extinct. In sexual organisms, the relevant question is whether or not the two daughter species can mate with one another. TxMCJ 01:15, 18 April 2007 (UTC)
- It is a big difference, but between the extremes of micro- and macroevolution there are always intermediary cases; closely-related species can breed in some cases, while in other cases members of the same species are unable or unwilling to interbreed for one reason or another. Just look at ring species to see that the line between species is often a matter of degrees in practice: there is never a case in which a parent is a different species from its offspring, so it is only after-the-fact that species can be distinguished, and it is never possible to draw a non-arbitrary hard and fast line. Species divisions are approximations; the only reason the species model is useful at all, in fact, is because there are few enough borderline cases (because the borderline populations have gone extinct or developed in new directions over time) to make species seem obviously different. But, again, this is only evident after-the-fact (and sometimes not even then); consequently, the line between microevolution and macroevolution is also one of subtle degrees, not a clear, hard-and-fast division.
- And yes, there are many observed instances of speciations; see speciation. Likewise, there are many traces of past macroevolution. The fossil record shows progressions between morphologically and genetically similar species illustrating evolutionary lineages. -Silence 01:07, 18 April 2007 (UTC)
- Maybe from this point on, refer to FAQ or to the article iself... (?) TxMCJ 01:15, 18 April 2007 (UTC)
The anonymous user is also using a definition of species (two species are different if they cannot mate and produce fertile offspring) that is a practical definition of very limited use. For what it is worth (if my reading of the anon. user is right), this gets to an issue that is central to Darwin's break with earlier natural historians and one of his most important contributions to biology: rather than seing species as ideals (which is how Linneus saw them), Darwin saw them as statistical phenomena (this means that variation among individuals poses neither philosophical (is it really a finch?) nor clasificatory probelms (is it a real finch?); it also means that we shouldn't be surprised that actual boundaries between species can be blurry ... this may be the case for transitional individuals; it also whi you can find a series of interbreeding populations and find among them individuals that cannot interbreed) . Creationism relies - at least implicitly - on the earlier view of species (there is an "ideal" lion, individuals that depart from this ideal are somehow flawed, the boundary between lion and other species is fixed and immutable for all time). I know I am being overly wordy but I think this issue needs to be explained clearly in either this article or FAQ or some other linked article. Most people today, even non-biologists, think of species as ideal types; biologists do not - and this is often a source of misunderstanding and confusion. Slrubenstein | Talk 11:34, 18 April 2007 (UTC)
- There should be an operational definition of species. Now a dog can physically mate with a cat but of course nothing will result because of the genome differences. Even if we test tube it. Is there not a measurable method to determine different species? There must be something in the genome structure that we could examine to see that without knowing anything else about the organism. The point of all of this is that macroevolution is a distinctly different than micro since it results in a new species by whatever definition of species you want to use. 69.211.150.60 13:03, 18 April 2007 (UTC)
- Macroevolution is different from microevolution, but it's not always "distinctly" different for the simple reason that there are indistinct, blurry "middle-ground" phenomena that are somewhere between microevolution (below a species level) and macroevolution (at or above a species level), as a consequence of the similar blurriness of the "species" designation (and specifically of the borders between different, supposedly "distinct" species).
- The definition of a species is not whether they can mate, but whether they can reproduce fertile offspring. Cats and dogs cannot produce fertile offspring, so they are different species; wolves and dogs can produce fertile offspring, so they are the same species. The problem arises in that sometimes some members of a species can reproduce with another species, while others cannot; that sometimes species usually produce infertile offspring, but sometimes produce fertile ones (e.g., in lions and tigers); and that data isn't always available on whether two species can produce fertile offspring or not. -Silence 19:03, 18 April 2007 (UTC)
yes that is my point. microE can be darker spots in a dogs litter where MacroE is another species. sure there might be some grey areas. now my difficulty is when exactly does a mutation happen so that one organism cannot mate with another. would it not take one female and one male getting the same mutation at the same time so they could mate with each other and not with their parents? this would happen at once correct? 68.109.234.155 19:09, 18 April 2007 (UTC)
- As Evolution currently states: "Large chromosomal rearrangements do not necessarily change gene function, but do generally result in reproductive isolation, and therefore cause speciation." If two species are closely related, they may be able to reproduce, but their hybrid offspring will not be fertile due to mispairings of chromosomes during meiosis.
- So, to summarize: as populations evolve, sections of their chromosomes switch from location to location on the genome, which increases the rate of sterile offspring between those with and without the chromosomal differences by leading to chromosome mispairings during reproduction, which discourages the interbreeding between populations with these different chromosomes and thus causes these populations to diverge further, which causes the chromosomal differences between the two to accumulate even more and thus further increases the rate of infertility, until finally it's highly unlikely or impossible for fertile offspring to result, and the two are considered separate species. This process is often sped up by geographic isolation, which, obviously, would make it impossible for the separated populations to interbreed at all, and thus would make speciation inevitable (unless the isolation period is very short—e.g., thousands rather than millions of years). -Silence 19:33, 18 April 2007 (UTC)
- So, the reason a female and male wouldn't need to get the same mutation at the same time is because infertility (and hence species division) isn't a black-and-white, 0% or 100% issue: a few minor genetic changes aren't necessarily going to cause infertility, but it's as these changes accumulate that divisions arise. And such accumulation is inevitable because mutation is so common, so speciation is similarly inevitable, though it doesn't always involve cladogenetic splitting-off of the type we've been discussing: a population can also develop as a whole into a new species through anagenesis. This is obviously more difficult to identify, though. -Silence 19:45, 18 April 2007 (UTC)
- 'which increases the rate of sterile offspring between those with and without the chromosomal differences by leading to chromosome mispairings during reproduction,' where can we see this grey area today? a population with these sterile offspring? etc? 68.109.234.155 23:00, 18 April 2007 (UTC)
- Mule, Liger, Tigon are known examples; and since the populations are largely sterile, they are of course very small. There are likely many examples in nature, but they would be too subtle and wouldn't last long enough to be noticed by anyone... let alone a biologist that happens to be walking by. - RoyBoy 800 23:35, 18 April 2007 (UTC)
- Speciation and microevolution is so slow and unusually subtle in its changes, that it takes an isolated population a significant amount of time to be truly genetically incompatible with its related species. Once something like that does happen, then you could call that change macroevolution... though more often than not it involves many smaller changes, rather than on significant change. After all biology is a very plastic medium. - RoyBoy 800 23:43, 18 April 2007 (UTC)
- But should we not see many example of this right now in all the thousands of species that are alive. Should there not be say at least 1% that are going throught this speciation process? 68.109.234.155 23:40, 18 April 2007 (UTC)
- Technically 100% of species are speciating, however if the population isn't isolated you wouldn't notice it. Take for example this hypothetical. Babies, one is "normal" and the other "abnormal" and has exactly twice the neurons as the other because of one key gene being repeated. If this allows the "abnormal" baby to out compete the other, the "normal" baby will die out or reproduce less and eventually go extinct and the "abnormal" genes become the "normal" standard for the species. Do this again, but have one isolated from the other... eventually you will have different species; or at least sub-species that do not normally interbreed. Once that happens speciation continues until you do get separate incompatible species. Without an isolated population, you cannot see it happening. - RoyBoy 800 23:50, 18 April 2007 (UTC)
- Also there is no basis (apart from statistical deviations, which is what I'm assuming you are referring to) to say that 1% of the species out there have grey areas. That is dependent on time and geographic isolation. If a continent separated, for a while you have a very high percentage of species in that area (on opposite sides of the new rift) that are closely related and compatible. Over time and as they become distinct from one another that percentage would slowly go down. - RoyBoy 800 23:55, 18 April 2007 (UTC)
- Yes but there should be some examples that we can see right now. At some point there is a situation where there is a mutation like the one you mentioned above. And according to what you are saying humans should speciate someday into at least 2 different species. If a mutatant develops a much more efficient brain would not they out compete the others. And why did not some dinosaurs develop speech? They would have had an advantate in hunting. Or why were they not 'smart' dinosaurs? We developed 'smartness' in only what 10 million years. The dinos had more time. Where was their tools etc. ? 68.109.234.155 00:02, 19 April 2007 (UTC)
- There are answers to these questions, but this is not the place to answer them... as this talk page is focused on improving the article, not talking about evolution generally. Could we please use your talk page? - RoyBoy 800 00:17, 19 April 2007 (UTC)
Back to editing
Now that the edit wars have cooled, and a few of the POV-pushing editors have either been banned, blocked, or are taking a vacation, can we get back to what we are trying to do, that is, get this article to an FA status. There are kilobytes of discussion above, a lot of it not so much fun to read, but I think we're somewhere at getting this article cleaned up and reorganized. Can some please post an outline or something of what is still required? It almost feels like this article should be reverted back a few weeks, and we start once again, but that might be the worst choice. Orangemarlin 21:28, 17 April 2007 (UTC)
My current rough proposal for the article layout is available at Talk:Evolution/Outline6. As I see it, our current main tasks are:
- Trim unnecessary details from Heredity, Mutation, Recombination, Hybridization and horizontal gene transfer, Speciation and extinction, and Evidence for evolution (now under Common descent and the Homologies).
- Add concrete observations and clear explanations for them throughout Heredity, Variation, and Mechanisms to help ground the concepts more for our readers and to explain the evidence for various theories.
- Clarify and simplify various sections, especially Gene flow and Genetic drift.
- Add a little information on exaptations to "Adaptation" section, and a lot of information on competition and limited resources to "Competition and cooperation".
- Improve the lead section more, making it clearer and better-flowing.
- Add section on phylogeny and systematics at end of "common descent"; some information can be incorporated from other sections, particularly dealing with molecular evidence.
- Add information on recent and current issues, controversies, and research in evolutionary biology, e.g., neutral mutation, punctuated equilibrium.
- Add information on the social impact of evolutionary theory beyond the "controversies" section, e.g., evolution in popular culture.
- Improve and add references and inline citations.
For a more in-depth, albeit slightly out-of-date, look, see Talk:Evolution/Archive_35#Expanded_to-do_list. -Silence 22:18, 17 April 2007 (UTC)
The article, possibly in response to critics, has introduced a lot of supporting evidence, which is difficult to organise sensibly. Now, from the discussion, it is evident that the most vociferous of the critics are unlikely to be swayed by mere facts, and it was an error to pander to them and hence spoil an otherwise fine article. The article is restricted to a description of the theory and its background, and makes no pronouncement of truth or falsity at all. Where there is controversy, the article, quite properly, restricts itself to statements that the controversy exists, but takes no side. It is refreshing to find a presentation which does not have the evangelical zeal of so many modern works on the subject. Gordon Vigurs 07:00, 18 April 2007 (UTC)
More to History??
I have mentioned this article before because the intro does a good job of describing issues of the Modern Synthesis and issues of molecular evolution:Nei M. Selectionism and neutralism in molecular evolution.Mol Biol Evol. 2005 Dec;22(12):2318-42. Epub 2005 Aug 24. Erratum in: Mol Biol Evol. 2006 May;23(5):1095. I know you can't cover everything but some mention of Morgan and Kimura would be nice. It is an opportunity to put mutation, neutral molecular evolution, natural selection, and population genetics into a relational perspective. Yeah, I know, too detailed. I applaud the cooperative effort and excellent discussions generated by the editors. GetAgrippa 12:06, 18 April 2007 (UTC)
Happy Birthday Clarence Darrow
A bit of an off-topic note... today is Clarence Darrow's birthday. He was the defending attorney at the Scopes Monkey Trial. The script of the play and film Inherit the Wind uses actual trial transcripts in the courtroom scenes, oftentimes using the exact words that were spoken by Darrow and Bryan (although the play and film both take some creative liberties as well). Spencer Tracy pulled off a remarkable portrayal of Darrow in the first version of the film. Clarence Darrow was a true intellectual whose courtroom arguments in defense of Scopes were powerful and sound. This is a fascinating chapter of American History and I encourage you to have a look at it if you're interested. Thanks, TxMCJ 17:55, 18 April 2007 (UTC)
- Guys, for future notice stuff like this and the "Moment of silence for Kurt Vonnegut" and the like would probably be better-placed at Wikipedia talk:WikiProject Evolutionary biology. This talk page is solely for discussing the Evolution article, not for notifications of any kind that might be of interest to evolution-involved editors. -Silence 18:56, 18 April 2007 (UTC)
- No problem -- thanks for the advice. Will crosspost and keep this kind of thing off this page in the future. Although a mention of the Scopes trial (or at least a link to it) might fit in the article somewhere (although admittedly that wasn't my point in posting this...) Thanks, TxMCJ 19:13, 18 April 2007 (UTC)
- Perhaps under "social effect", if we decide to expand our coverage of creationism (which I'd been considering, to address things like intelligent design). Probably not, though, since isolated incidents like the Scopes trial aren't very enlightening outside of their historical context, and providing the context alone will probably take up a lot of space. -Silence 19:18, 18 April 2007 (UTC)
- Speaking of monkeys, maybe chimps is a bit off topic, but Chimps More Evolved Than Humans struck me as interesting, describing the effect of genetic drift in small populations. .. dave souza, talk 20:03, 18 April 2007 (UTC)
- I think there is also a hypothesis or some evidence that all living chimps are descended from a Founder effect of resistance to a HIV-like virus as I recollect reading. GetAgrippa 01:15, 19 April 2007 (UTC)
- Erm. Well, from that crappy summary, I garner that it's not talking about drift but about positive selection. I can't find the actual paper on the PNAS website - anyone got a link? Graft | talk 21:26, 19 April 2007 (UTC)
- I couldn't find the PNAS article either, but did find other related articles. It must be an early release for online PNAS subscribers only. Weird?GetAgrippa 00:12, 20 April 2007 (UTC)
Charles Darwin made FA today
Just in case you skip the main page and head right over to fight the Evolution-Creation wars. I'm watching the article, just to see what creative vandalism is employed. Not much interesting so far. Orangemarlin 00:42, 19 April 2007 (UTC)
- OOOOOoooops. Just noticed the warning in the previous conversation. Sorry. Orangemarlin 00:42, 19 April 2007 (UTC)
- That's OK, this is at least much more directly relevant to the Evolution article, considering the immense importance of the Charles Darwin article to this one. We should expect some more activity around this article in the near future, as a side-effect of the greatly increased activity at that article; with that in mind, it may be sensible to un-semiprotect this article, for the same reason that FAs are unprotected when they appear on the main page: we'll get a lot of new users here who may be lured into becoming future Wikipedia editors if given a chance to experiment a little. I think the long-term benefits of that outweigh any short-term vandalism concerns. -Silence 05:26, 19 April 2007 (UTC)
"See also"
Guys, I have to admit I liked it better when we had a short "see also" section rather than trying to cover every conceivable aspect of the topic in stubs inserted in the main body. I know it's a pain to keep reverting people who well-meaningly insert long lists of links to relevant topics, but hopefully, placing a comment in capital letters in the wikitext will stave off some of the flood. For instance, it would be far preferable to have a link to evolutionary biology rather than devote an entire section of the article to unsupported speculation of what the scope of different subfields is and how they are related to each other. Samsara (talk • contribs) 09:31, 18 April 2007 (UTC)
- We already have links to Evolutionary biology at both the top and bottom of the article, through the use of templates. A "see also" link would thus be entirely redundant. The reason we have (and clearly should have; no one except you has ever in the history of the article agreed on the point that a discussion of the scientific field studying evolution is out-of-place in the evolution article!!) a section on evolutionary biology is because it's immensely important and relevant (much more so than the "social effect" section!), not because we're looking for an excuse to provide yet another link to it.
- If you think the section has "unsupported speculation", then add references and note any dubious unreferenced information; improve the section, don't continuously mass-delete it in flagrant disregard for consensus and the entire editorial process. -Silence 14:09, 18 April 2007 (UTC)
- Dude, don't lecture me on policy. Just because I'm the first to criticise the inclusion of that section doesn't discredit my point. The article is about evolution, not the study of it. Separate article, please. And just to return the favour, please remember WP:OWN. Thanks. Samsara (talk • contribs) 20:01, 18 April 2007 (UTC)
- Yes, this article is about evolution, but clearly the study of evolution is relevant to an article on evolution! I see no problem with shortening the current section (and, indeed, I already proposed doing exactly that above), but deleting it altogether is even more absurd than deleting, say, the "social effect" section (which this article also isn't "about", since it's about evolution, not the social impact of evolutionary biology).
- And, um? I'm not "lecturing you on policy"; I didn't even cite any policies above. I simply disagreed with your point, and explained why. I didn't say that the fact that you're the first to criticize the inclusion "discredits your point"; I merely pointed out, correctly, that you should wait for some degree of consensus (or at least a little discussion!) before rushing to (repeatedly) mass-delete a major section of a high-profile article. I didn't say that you're wrong because no one else has done what you did before; that would obviously be absurd, and Wikipedia relies on people doing things that no one's done before. Rather, I pointed out that all past editors have seemed to support the section, and therefore you should discuss the issue rather than immediately assuming that one editor (yourself) is necessarily correct, while everyone else who's worked on the section as been wrong.
- There is no "favor" to return, as I didn't quote any policy at you, although WP:OWN would be much more appropriately ascribed to you than to me, as I haven't claimed that my own personal opinion outweighs editorial consensus; hell, I didn't even revert your last change, because I wanted to give you time to make your case—though I'll do so now!
- Your comment suggests that you didn't read my comment, and that your time would be better-spent reviewing Wikipedia's WP:CIVIL policy than mass-deleting other editors' work without any discussion. Even I didn't do that, and my recent reorganization efforts on this article have been much more severe than yours—plus I discussed all major changes here first. Please reconsider this antagonizing and bullying of other editors; Wikipedia relies on discussion, not revert-wars. -Silence 21:54, 18 April 2007 (UTC)
- Samsara, I really appreciate your blunt honesty, especially with regards to Creationist POV sneaking into articles. I wish you were around a few days ago for some of the crap happening here and in the Intelligent Design article. However, although I agree that shortening the natural selection part is useful, I'd hate to waste the good writing, and since natural selection is a critical part of the evolutionary process (if not the only part of the process), isn't cutting out as much as you wish defeating the clarity and the science of the article? I really hate seeing two pro-Evolution editors arguing so strongly, when the creationist POV is sneaking into so many articles. Orangemarlin 00:47, 19 April 2007 (UTC)
- This dialogue illustrates my suggestion for a "constitution" to develop this article is a good idea. The constitution would be a plan and rules to implement the plan. It is bad enough to deal with vandals and creationist-I.D. distractions without conscientious editors arguing. If all could agree on a constitution then everyone can argue the details as the article develops. At least the article would finally have structure. The plan aspect of a constitution is moving along, however the rules for implementation and development needs more than standard Wikipedia rules. Even if this article develops to FA quality and excellence in science standard it will still morph into crap within a few months because there is no structure and framework for an excellent article. The standard of "good" and "bad" article (and whatever that means)will always drive change. GetAgrippa 13:46, 19 April 2007 (UTC)
- Which is a good thing. This article will always need to adapt, and most of those adaptations, in the long run, are for the best: just looking at the quality of this article even when it was first accepted as an FA is embarrassing, compared to our current expectations. The same will probably eventually hold true for an article of high quality today, for various reasons. The only "constitution" we should rely on are the policies and goals of Wikipedia, applied to the topic of evolution. If we need much more than that, we're deviating too far from Wikipedia as a whole. The cause of the above dispute was simple: Samsara has some personal grievance with the Evolution editors and with Wikipedia as a whole, so he decided to stir up some trouble by making an overly "extreme" edit without discussing the matter first. We don't need a constitution to resolve one editor's personal problems, especially if that editor is more interested in whining than in discussing practical solutions. Let's just get back to actually improving the article. -Silence 02:09, 20 April 2007 (UTC)
- This dialogue illustrates my suggestion for a "constitution" to develop this article is a good idea. The constitution would be a plan and rules to implement the plan. It is bad enough to deal with vandals and creationist-I.D. distractions without conscientious editors arguing. If all could agree on a constitution then everyone can argue the details as the article develops. At least the article would finally have structure. The plan aspect of a constitution is moving along, however the rules for implementation and development needs more than standard Wikipedia rules. Even if this article develops to FA quality and excellence in science standard it will still morph into crap within a few months because there is no structure and framework for an excellent article. The standard of "good" and "bad" article (and whatever that means)will always drive change. GetAgrippa 13:46, 19 April 2007 (UTC)
- Samsara, I really appreciate your blunt honesty, especially with regards to Creationist POV sneaking into articles. I wish you were around a few days ago for some of the crap happening here and in the Intelligent Design article. However, although I agree that shortening the natural selection part is useful, I'd hate to waste the good writing, and since natural selection is a critical part of the evolutionary process (if not the only part of the process), isn't cutting out as much as you wish defeating the clarity and the science of the article? I really hate seeing two pro-Evolution editors arguing so strongly, when the creationist POV is sneaking into so many articles. Orangemarlin 00:47, 19 April 2007 (UTC)
- I disagree. I have noted many academics leave Wikipedia in frustration. Many believe the mechanics of Wikipedia is failing as in the Wikipedia:Wikipedia is failing essay. Wikipedia has absolutely no credibility with academics or the public in general. I personally like the idea, but I have to agree that it doesn't seem to be working. I personally hope that Wikipedia evolves a new and better way. GetAgrippa 11:48, 20 April 2007 (UTC)
- Which comment are you replying to with this comment? The indention implies you're replying to Samsara. And what does this have to do with our discussion above? This Talk page is for discussing Evolution, not for implementing new general Wikipedia-wide policies. -Silence 14:10, 20 April 2007 (UTC)
Unexplained deletion
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I noticed the large section below was deleted a few edits back with "spelling" as the explanation. Seems like obvious vandalism but I thought I'd put it here instead of reverting since it looks like you guys are in the process of overhauling the article. Aelffin 13:08, 18 April 2007 (UTC)
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Modern research
Academic disciplines
Scholars in a number of academic disciplines continue to document examples of evolution, contributing to a deeper understanding of its underlying mechanisms. Every subdiscipline within biology both informs and is informed by knowledge of the details of evolution, such as in ecological genetics, human evolution, molecular evolution, and phylogenetics. Areas of mathematics (such as bioinformatics), physics, chemistry, and other fields all make important contributions to current understanding of evolutionary mechanisms. Even disciplines as far removed as geology and sociology play a part, since the process of biological evolution has coincided in time and space with the development of both the Earth and human civilization.
Evolutionary biology is a subdiscipline of biology concerned with the origin and descent of species, as well as their changes over time. It was originally an interdisciplinary field including scientists from many traditional taxonomically-oriented disciplines. For example, it generally includes scientists who may have a specialist training in particular organisms, such as mammalogy, ornithology, or herpetology, but who use those organisms to answer general questions in evolution. Evolutionary biology as an academic discipline in its own right emerged as a result of the modern evolutionary synthesis in the 1930s and 1940s. It was not until the 1970s and 1980s, however, that a significant number of universities had departments that specifically included the term evolutionary biology in their titles.
Evolutionary developmental biology (informally, evo-devo) is a field of biology that compares the developmental processes of different animals in an attempt to determine the ancestral relationship between organisms and how developmental processes evolved. The discovery of genes regulating development in model organisms allowed for comparisons to be made with genes and genetic networks of related organisms.
Physical anthropology emerged in the late 19th century as the study of human osteology, and the fossilized skeletal remains of other hominids. At that time, anthropologists debated whether their evidence supported Darwin's claims, because skeletal remains revealed temporal and spatial variation among hominids, but Darwin had not offered an explanation of the specific mechanisms that produce variation. With the recognition of Mendelian genetics and the rise of the modern synthesis, however, evolution became both the fundamental conceptual framework for, and the object of study of, physical anthropologists. In addition to studying skeletal remains, they began to study genetic variation among human populations (population genetics); thus, some physical anthropologists began calling themselves biological anthropologists.
The capability of evolution through selection to produce biological processes and networks optimized for a particular environment has greatly interested mathematicians, scientists and engineers. There has been some recent success in implementing these ideas for artificial uses, including genetic algorithms, which can find the solution to a multi-dimensional problem more quickly than standard software produced by human intelligent designers, and the use of evolutionary fitness landscapes to optimize the design of a system[1] Evolutionary optimization techniques are particularly useful in situations in which it is easy to determine the quality of a single solution, but hard to go through all possible solutions one by one.
Article milestones
Perhaps "Article milestones" at the top could contain a link or two to the prefered version(s) of longtime editors of this article that feel it has gotten worse or that there is something special to recommend that previous version. WAS 4.250 16:39, 23 April 2007 (UTC)
- I don't think this article's ever been consistently high-quality enough for there to be much of a point in isolating a version for general quality. On the other hand, we might isolate versions that have high quality in specific areas (e.g., a certain layout, certain well-done sections, certain images, and other things that might have subsequently deteriorated), which we can use to improve the current section. Although I don't think the article, taken as a whole, has ever been a lot better than it is today (and if it is, that's only because the current article layout and contents are in a transitional period following a major restructuring and reprioritization), I do think there are many aspects of the article that were better at various times. -Silence 16:49, 23 April 2007 (UTC)
Asexual to sexual
How did organisms go from asexual reproduction to sexual reproduction? —The preceding unsigned comment was added by Rhydd Meddwl (talk • contribs) 22:59, 23 April 2007 (UTC).
- You should know better than this, Rhydd Meddwl!;) Please add new comments to the end of the page! Now, this isn't a big problem at all: there are clear evolutionary advantages to sexual reproduction. For its origins, see here. garik 01:55, 24 April 2007 (UTC)
- In eukaryotes it's generally the other way around -- asexual lineages are well-rooted within sexual lineages, and tend to be less diverse TxMCJ 04:28, 24 April 2007 (UTC)
- What the...? This is a HUGE problem. Even the page you linked to says, first off, "The evolution of sex is a major puzzle in modern evolutionary biology." Graft | talk 17:58, 24 April 2007 (UTC)
- Well, OK, I did overstate that rather; you're quite right – I don't know what I was thinking when I wrote it. On the other hand, I'm not convinced that that first line doesn't overstate its case somewhat too. The difficulty of testing hypotheses makes research into the origin of sexual reproduction very hard, but it's certainly not a major puzzle in the sense that no one has any idea how it might have happened. And it's also not a problem at all for evolutionary biology, in the sense creationists sometimes claim (i.e. they can't see how sex could have originated, so it must have been through design etc.). But yes, there are of course also clear advantages to asexual reproduction. garik 23:49, 24 April 2007 (UTC)
- What the...? This is a HUGE problem. Even the page you linked to says, first off, "The evolution of sex is a major puzzle in modern evolutionary biology." Graft | talk 17:58, 24 April 2007 (UTC)
Natural selection of rate of mutation?
A creationist, the other day, put the following to me: supposed declining health and lifespans (yes, from an analysis of the Bible) are due to the iterative passing on of mutations throughout the last 6,000 years (again Bible study). In other words, natural selection, rather than contributing the spread of advantageous mutations, has not succeeded in filtering out deleterious ones. Now, I don't buy this, for both factual and theoretical reasons. But it got me thinking: the force of natural selection, for it to work, has to be stronger than whatever forces of mutation (by whatever means). (*Speculation*: Which, from what I gather from thinking about it, means that there would be a naturally selected "ideal" rate of mutation (by means of DNA repair mechanisms etc.).) My question is: am I thinking about this wrongly, and if not, is there literature on this already? Jameshfisher 23:54, 25 April 2007 (UTC)
- Indeed there is, organisms have even evolved variable mutation rates. link and link TimVickers 00:05, 26 April 2007 (UTC)
Credibility, and controversy
Evolution is a Theory but in this article it is discribed as fact, this needs to be rectified, also things such as Ireducible complexity (bacterial flagellum motor etc.) that provide hurdles for evolution theory should be included into the article... 124.181.46.194 01:17, 26 April 2007 (UTC)
- First, you are misunderstanding what the term theory means in science. Theory does not mean guess but rather a well-tested hypothesis with broad explanatory power. Evolution is a theory in the same way that gravity is. Second of all, the overwhelming scientific consensus is that evolution occured and that claims such as Behe's regarding the bacterial flagellum have no basis. As such , Wikipedia's undue weight clause of the neutrality policy comes into play. JoshuaZ 01:58, 26 April 2007 (UTC)
- You are a better man than I Joshua. This BS is getting really old, and I've been doing serious editing for only 4 or 5 months on these articles. I think I'm just reading to tell them to all screw off. Orangemarlin 02:19, 26 April 2007 (UTC)
- I start to wonder if people are being difficult on purpose, or if they do not know how to read, or just like to parrot nonsense some preacher spewed from the pulpit and repeat it in a brainless fashion without giving it any thought whatsoever. I agree with OM. This gets old. Very old. Please people, use your heads. Read. Think. It is the reason God gave you a brain; to use. --Filll 19:51, 26 April 2007 (UTC)
- I believe that it takes people that 'think' to not accept propositions put out by the main stream, establishment science. Most of our great discoveries were made by those who doubted the mainstream beliefs in science. 'Parroting' dogma without allowing questioning of any sort is certainly 'brainless'. 'Please, people' believe what you are told without question. 68.109.234.155 21:44, 26 April 2007 (UTC)
- And you believe I don't "think". My training has been, for at least 30 years, to examine everything with a critical eye. I've read and studied more biology than you could imagine, and if I thought at any point something didn't make sense, I would ask questions. Yes, great ideas come from question the status quo. That would be Darwin challenging the prevailing Christian viewpoint, or Gallileo challenging just about everything that was said. All the evidence, not just 99.9%, but all fit the theory of Evolution. Yes, I'm smart enough to know that maybe someday some piece of evidence will arise that will through the whole theory into doubt. Maybe we will find a fluffy bunny rabbit in Precambrian rocks. Orangemarlin 23:39, 26 April 2007 (UTC)
Question posted on FAQ
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Moved from Talk:Evolution/FAQ [4]
Thanks for the question. In general Wikipedia article talk pages are intended for discussion of how to improve the article, rather than general discussion on the topic. You may have better luck with Wikipedia:Reference desk for these types of questions. Briefly, however, there is a distinction between abiogenesis (life from non-life) and evolution of living creatures. This distinction is important since there is different evidence for each. The former is (probably) a rare event, and fairly speculative, while the latter is well established. The specific experiment you're refering to is probably Miller/Urey. While perhaps many scientists do believe some form of abiogenesis, this is not a component of evolution. You may want to ask this question again at the reference desk for a more detailed response. --TeaDrinker 15:23, 26 April 2007 (UTC)
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To do list
Please note at the top, there is a to-do list to get this article back to FA status. Please strike through any tasks that you've accomplished, or you've noticed accomplished. There was an edit conflict (my fault), and I'm not sure who archived the to-do list, but thanks! Orangemarlin 18:23, 27 April 2007 (UTC)
- I'm going to be making an effort to thoroughly reference and clarify this article, hopefully we can bring this core topic it back to FA level. TimVickers 01:46, 28 April 2007 (UTC)
- I am so impressed with this organizational approach to improvement; a stroke of brilliance. It should eliminate most of the eclectic debates that plague this page. Well done and much luck. --71.77.209.218 00:57, 29 April 2007 (UTC) Random Replicator
- And, oh look, somebody else seems to think that the academic disciplines section needs to go, like I've repeatedly said and repeatedly been reverted. Is there anything nice I can say about that? Don't think so. Samsara (talk • contribs) 01:15, 29 April 2007 (UTC)
- I like you Samsara. You get right to the point, without worrying about BS. I hate that section, so will you help me if I delete it? Orangemarlin 01:45, 29 April 2007 (UTC)
- Yes, let's do it! Samsara (talk • contribs) 21:31, 29 April 2007 (UTC)
- By the way, what's a good size for an FA? We're at 80 KB for this article, which may be just right. Orangemarlin 01:52, 29 April 2007 (UTC)
- About 40-60kb of readable text is good, the total size of the article will probably pass 100 kb when it is fully referenced. What about replacing the "academic" section with a summary of current areas of research in evolution? Origin of sex, genetic basis of speciation and the influence of developmental biology on the direction of adaptation come to mind, but I'm sure there are others. I think it is important to convey that this is an area of current research. TimVickers 02:56, 29 April 2007 (UTC)
- The challenge is to enforce a moving wall in the spirit of WP:DUST. People will repeatedly want to include research that came out last week, and I'm of the firm conviction that this is not appropriate for an encyclopaedia. My suggestion for the wall period is five years. That will still give us lots of exciting stuff to talk about, if we want to go down that road. Samsara (talk • contribs) 21:31, 29 April 2007 (UTC)
The heck?
Why are comments listed in the "To-do" section as though they were mine, when I've said exactly the opposite in some cases? An absurd "9. Academic disciplines." comment is interjected right before "-Silence 06:17, 13 April 2007 (UTC)" as though it were my idea. Very, very strange. -Silence 18:30, 30 April 2007 (UTC)
- My fault. I just cut and pasted, and I must have carried over your signature. And it was my comment on the academic disciplines. Several of us didn't want that section in there. Orangemarlin 18:38, 30 April 2007 (UTC)
- I think the original cut an paste was mine. Apologies if attributions got mixed up. David D. (Talk) 20:40, 30 April 2007 (UTC)
- Oh so you were the edit conflict this weekend trying to create the to do list. I was all confused as to what happened!!! LOL. Orangemarlin 21:42, 30 April 2007 (UTC)
- I thought you knew? I should have guessed not by the absense of flaming on my talk page ;) David D. (Talk) 21:49, 30 April 2007 (UTC)
- I won't discriminate. Now that I know, I'm head over there right now for some serious flaming!!!! I couldn't figure out what happened on Saturday. The history didn't show anything, because of the edit conflict, so I couldn't tell who did it. But now that I know...... Orangemarlin 23:18, 30 April 2007 (UTC)
- I oppose the removal of the "academic disciplines" section, and at least a few other editors seem to as well. I would like to see some damned good reasoning for this mass-deletion, and perhaps a straw poll to determine consensus, since Orangemarlin and Samsara seem to have assumed that "two people agreeing during a brief interim when everyone else is too busy to complain = consensus". -Silence 23:57, 30 April 2007 (UTC)
- This is no fun. Revert it if you like. Orangemarlin 00:13, 1 May 2007 (UTC)
- I'd support the replacement of the "Academic areas" section with a summary of current research and research topics. Some of the content could be re-used, but the focus should be changed. TimVickers 01:36, 1 May 2007 (UTC)
- I think the major academic areas are also worthy of discussion, though I'd support trimming off the less prominent or essential ones. Understanding what fields evolution is studied in will help people better understand evolution, because it will demonstrate the wide scientific applicability of the basic ideas detailed throughout the rest of the article. In my article outline, I recommended a section like "Current research", with "Academic disciplines" as either a subsection or a couple of paragraphs in the larger section. (This section was originally planned to be a part of the larger "Study of evolution" section alongside "History of evolutionary thought", but when it was decided that History would be moved to the top of the article, this plan was scrapped.) -Silence 02:14, 1 May 2007 (UTC)
- Excellent, a new section entitled "Current research" would work very well. Perhaps we could merge the two by giving one example of a current research topic for each area?
Outline of "Current research" section
Scholars in a number of academic disciplines continue to document examples of evolution, contributing to a deeper understanding of its underlying mechanisms. Every subdiscipline within biology both informs and is informed by knowledge of the details of evolution, such as in ecological genetics, human evolution, molecular evolution, and phylogenetics. Areas of mathematics (such as bioinformatics), physics, chemistry, and other fields all make important contributions to current understanding of evolutionary mechanisms. Even disciplines as far removed as geology and sociology play a part, since the process of biological evolution has coincided in time and space with the development of both the Earth and human civilization.
Evolutionary biology
What was the last universal common ancestor?Level of selection - gene-centric view and group selectionEvolution of sexPunctuated equilibrium
Evolutionary developmental biology
The importance of mutations in developmental pathways in adaption link
Population genetics
Artificial life and in silico evolution
- Application of evolutionary algorithms to solve mathematical problems such as NP-complete problems.
- Computer modelling of the evolution of organisms.
Comments? TimVickers 03:04, 1 May 2007 (UTC)
Genetic drift versus natural selection
Is there a reason that the genetic drift section is presented before the natural selection section? My understanding (forgive me for being a clueless amateur here) is that natural selection is overall more important as a driver of evolution. It is definitely better-known and easier to understand. Kla'quot 07:31, 1 May 2007 (UTC)
- None of the sections in this article are presented in order of importance. They're all too important, and too intricately connected, to make a "most-to-least-important" sequencing useful or effective. Genetic drift is presented before natural selection because it's in some ways the "baseline" effect, the inevitable statistical effect outside of any environmental context, whereas selection is the more exceptional and context-variable effect; to make up for this, natural selection is explained in more detail in the lead section, so people who read through the article will have at least some grasp on the basics of selection before getting to "genetic drift". Another reason they're presented in that order is because it provides at least what seems to be a smoother transition between "gene flow" and "adaptation" (which is associated with selection). -Silence 15:55, 1 May 2007 (UTC)
descended from a single ancestral species?
Is this really a part of the theory, and should it be in the intro? There is now known to be a lot of horizontal gene transfer among the single celled organisms. Additionally, organelles such as mitochondria and chloroplasts are hypothesized to have once been independant living organisms. The shared genetic code would seem to suggest a shared ancestry, but perhaps there could have been a convergence on the same code once the symbiosis started. The single anscestral species hypothesis might be true, but does not seem essential to evolutionary theory.--Africangenesis 05:32, 30 April 2007 (UTC)
- Well, it's a significant part of it. Even organelles share the basic DNA code of the rest of the organism, so I would contend that mitochondria and chloroplasts share the same common ancestor. Common descent is a critical part of Evolution, and so far, not a single iota of evidence has been found to counter that theory. I dare say it is essential to Evolution. Orangemarlin 05:44, 30 April 2007 (UTC)
I don't think it's true that a single ancestral species is reqired for evolution, if life on earth had originated from two independent origin events, evolution would still have occurred and the life forms that would have been produced would still show adaptation etc. Evolution is entirely independent of the details of how life originated as it is just a description of how life changes over time. However, I agree that a single common ancestor fits the data best at present. TimVickers 16:06, 30 April 2007 (UTC)
- Yes, you're right. Should have written my comments more clearly. Orangemarlin 16:23, 30 April 2007 (UTC)
- There is a lot of interesting horizontal gene transmission and confusion of lineages in archaea, fortunately the eukaryote lineages are cleaner. Some evolution is not strict vertical descent. I don't mean to be critical of the intelligent designer, but we could have used a sprinkling of different genetic codes to reduce the ease of transpecific disease transmission. 8-) --Africangenesis 16:45, 30 April 2007 (UTC)
- I doubt it. But maybe one day they might find a random thing that might indicate something different, but right now everything lines up to a single common ancestor. Orangemarlin 16:59, 30 April 2007 (UTC)
- Yes... I really like the idea of multiple early origins of life on Earth (all of which ended up going extinct except for one)... but wouldn't it be awesome to find some kind of deep-sea chemoautotrophic ribozyme thingamajigs with a different genetic code and R-chiral amino acids someday... You never know, they could be out there somewhere, TxMCJ 05:21, 6 May 2007 (UTC)
Evolution FAQ: Level of Acceptance of Evolution among Scientists
Old discussion on Poll |
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First let me say that I am not a creationist or ID advocate--I am trying to evaluate both sides skeptically like a good critical thinker. I have a problem with the part in the Evolution FAQ on this talk page that says, "Evolutionary theory is not controversial in biology itself, where more than 99.84% of scientists accept it.[1][2]" Cited are references to a Gallup poll of scientists. Firstly, these are tertiary and secondary sources, respectively, the first referring to the second. Secondly, because of that I cannot know exactly what question was asked. Roughly 99.84% of American scientists may reject "creation-science," but that study was taken 20 years ago, and in that time ID has risen. ID (officially) is neither creation-science nor evolution. Furthermore, did that 99.84% actually reject all creation science or just YECism (which was making public splashes at that time, as in McClean vs. Arkansas)? The Newsweek author might not have realized the difference. I would just clip that statement out, but then there would be nothing left, so someone would probably revert me. I don't doubt that a significant majority of scientists are pro-evolution (just peel open any science journal). Does anyone wish to provide further evidence in defense of this poll, or a different meter of scientific acceptance? Otherwise, that statement needs to be revised or cut. Good day. Schmitty120 00:26, 3 May 2007 (UTC)
<reduce indent> OK Schmitty120, I don't think anyone, not me or any other editor, would be opposed to a reliable, verifiable, and peer-reviewed source challenging Evolution. Of course, the undue weight clause of neutral point of view would suggest that even mentioning one article challenging Evolution is not appropriate, because the 9 million other articles would not only be the consensus, but it would be the Neutral and Scientific POV. By the way, scientists are not overwhelmingly pro-Evolution as a matter of faith, they are overwhelmingly pro-Evolution because it is science. Orangemarlin 23:22, 7 May 2007 (UTC)
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descended from a single ancestral species?
Is this really a part of the theory, and should it be in the intro? There is now known to be a lot of horizontal gene transfer among the single celled organisms. Additionally, organelles such as mitochondria and chloroplasts are hypothesized to have once been independant living organisms. The shared genetic code would seem to suggest a shared ancestry, but perhaps there could have been a convergence on the same code once the symbiosis started. The single anscestral species hypothesis might be true, but does not seem essential to evolutionary theory.--Africangenesis 05:32, 30 April 2007 (UTC)
- Well, it's a significant part of it. Even organelles share the basic DNA code of the rest of the organism, so I would contend that mitochondria and chloroplasts share the same common ancestor. Common descent is a critical part of Evolution, and so far, not a single iota of evidence has been found to counter that theory. I dare say it is essential to Evolution. Orangemarlin 05:44, 30 April 2007 (UTC)
I don't think it's true that a single ancestral species is reqired for evolution, if life on earth had originated from two independent origin events, evolution would still have occurred and the life forms that would have been produced would still show adaptation etc. Evolution is entirely independent of the details of how life originated as it is just a description of how life changes over time. However, I agree that a single common ancestor fits the data best at present. TimVickers 16:06, 30 April 2007 (UTC)
- Yes, you're right. Should have written my comments more clearly. Orangemarlin 16:23, 30 April 2007 (UTC)
- There is a lot of interesting horizontal gene transmission and confusion of lineages in archaea, fortunately the eukaryote lineages are cleaner. Some evolution is not strict vertical descent. I don't mean to be critical of the intelligent designer, but we could have used a sprinkling of different genetic codes to reduce the ease of transpecific disease transmission. 8-) --Africangenesis 16:45, 30 April 2007 (UTC)
- I doubt it. But maybe one day they might find a random thing that might indicate something different, but right now everything lines up to a single common ancestor. Orangemarlin 16:59, 30 April 2007 (UTC)
- Yes... I really like the idea of multiple early origins of life on Earth (all of which ended up going extinct except for one)... but wouldn't it be awesome to find some kind of deep-sea chemoautotrophic ribozyme thingamajigs with a different genetic code and R-chiral amino acids someday... You never know, they could be out there somewhere, TxMCJ 05:21, 6 May 2007 (UTC)
- ^ For optimizing the design of a large interferometer array using an evolutionary fitness landscape, see Buscher, David (2003). "Interferometric "fitness" and the large optical array". Proceedings of the SPIE. 4838: 110–125. Retrieved 2007-03-17.
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