Talk:Speciation/Archive 2

Archive 1

Archive 2

TSE time for speciation effect

Heard about this in a paper from Wiens et al 2010 - I wonder how it fits in this article? — Preceding unsigned comment added by 188.23.194.10 (talk) 09:08, 24 June 2014 (UTC)

Darwin's Dilemma (and its resolution)

I am not certain what the requirements and expectations of an encyclopedic entry are. However, I am baffled by the contents of the subheadings under Darwin’s Dilemma

For instance, under the sub-heading The effect of sexual reproduction on species formation it is stated that the “The cost of rarity arises from the simple requirement of out-crossing sex that it takes two individuals to mate”. But nothing that follows this sentence explains how this solves Darwin’s Dilemma. A sexual creature simply mates with another individual of the opposite gender, and leaves Natural Selection to deal with the consequences. There is no “cost of rarity” in this equation, unless one has read and understood the assumptions made by the researchers who did the simulations that led to this conclusion. Without this prior knowledge (of the assumptions built into the models) one has to assume that new species can only form if like-is-attracted-to-like (i.e. that assortative mating is an evolutionary imperative). I am not too sure whether this is indeed an entirely universal imperative that can be applied to the majority of sexually reproducing creatures, and can therefore explain why sexual individuals are grouped into species - the phenomenon that puzzled Darwin.

Another interpretation of "The effect of sexual reproduction on species formation" section is that new species are constantly budding off a parent species, but small species are always at a disadvantage to larger species, because of the "cost of rarity". But this presupposes that the members of the daughter species are spread throughout the parent species (i.e. the same speciation event has occurred in multiple locations in the parent species, producing scattered individuals, who all belong to the same species, but are unrelated to one another. This seems unlikely). It is much more likely that speciation has occurred in a group in only one location, where the daughter species will therefore not be rare.

What I am trying to point out is that the section on "The effect of sexual reproduction on species formation" does not provide an explanation of the cost of rarity, and is only of use to a reader who is already familiar with the relevant literature and the arguments contained therein. The ordinary reader of Wikipedia does not have access to the references cited, and therefore learns nothing from this section. Oggmus (talk) 16:43, 2 August 2014 (UTC)

 Done Oggmus (talk) 05:31, 8 November 2014 (UTC)

Since replacing the cryptic sentence "The cost of rarity arises from the simple requirement of out-crossing sex that it it takes two individuals to mate" with an explanation of what this actually means, and how the cost is encurred, a new cryptic sentence has been inserted into the section. It is out of context, and provides no explanation or details: However, findings, published in the journal Current Biology, resolve "Darwin's dilemma": the sudden appearance of a plethora of modern animal groups in the fossil record during the early Cambrian period. I have removed it. If it is to be resurrected it might be more at home in the Wikipedia article on Punctuated equilibrium, which deals with "punctuated evolutionary events" like the "Cambrian explosion". Oggmus (talk) 13:07, 6 March 2015 (UTC)

This entire section is trying to reinvent the wheel. Darwin himself solved this dilemma in his own lifetime with a eureka moment, he described it in his autobiography as follows: "and I can remember the very spot in the road, whilst in my carriage, when to my joy the solution occurred to me.... The solution, as I believe, is that the modified offspring of all dominant and increasing forms tend to become adapted to many and highly diversified places in the economy of nature." This section is trying to give an unnecessarily complex explanation that misses the big picture and ignores what Darwin actually discovered from his years spent studying nature. If we're going to have a section called "Darwin's dilemma", then we should also provide "Darwin's solution." — Preceding unsigned comment added by 63.155.56.179 (talk) 06:50, 6 November 2016 (UTC)

Observed Speciation vs. Inferred Speciation

The normal meaning of "observe" in science is to observe in the course of an experiment. Multiple times in this article the claim is made that outside the laboratory speciation has been "observed". Each case then shows a case of inference (strong evidence consistent with a speciation model) but not observation. Why must it be so hard for scientists to admit the truth? Speciation has not been observed outside the laboratory. The time scale has not been long enough yet. A reproductive isolation definition of speciation would have American Indians be a different species of human after the glaciers melted. No one would argue that. Mrdthree (talk) 06:50, 1 October 2014 (UTC)

www.talkorigins.org claims it has a case that could count for observed speciation but there is no reference. Here is the quote provided without citation "Three species of wildflowers called goatsbeards were introduced to the United States from Europe shortly after the turn of the century. Within a few decades their populations expanded and began to encounter one another in the American West. Whenever mixed populations occurred, the specied interbred (hybridizing) producing sterile hybrid offspring. Suddenly, in the late forties two new species of goatsbeard appeared near Pullman, Washington. Although the new species were similar in appearance to the hybrids, they produced fertile offspring. The evolutionary process had created a separate species that could reproduce but not mate with the goatsbeard plants from which it had evolved." Mrdthree (talk) 00:11, 2 October 2014 (UTC)

Story is attributed to this article: http://www.scientificamerican.com/article/a-breed-apart/ 63.175.124.34 (talk) 22:00, 3 October 2014 (UTC)

talkorigins.org is not a reliable source

It is an altnet newsgroup. It has been removed. There is no contact email. The publisher refers to parties to a blog of cursing and argument if there are any questions on the blog's content. Mrdthree (talk) 23:48, 1 October 2014 (UTC)

Sexual selection

The lead jumps from natural selection to the statement "There is research comparing the intensity of sexual selection in different clades with their number of species.[5]" This is not connected either to the rest of the lead, or to any discussion in the body of the article. Something appears to be missing. Chiswick Chap (talk) 20:18, 16 January 2016 (UTC)

Hi Chiswick Chap, I totally agree that this sentence is out of place, and meaningless as it stands. But it does touch on an important subject that is missing from the Introduction. I will endeavor to turn it into a very short paragraph that can sensibly be included in the Lead section - but no promises that I'll succeed! Cruithne9 (talk) 08:49, 4 August 2016 (UTC)

Somebody, however, needs to write a new section on how sexual selection does produce species. A thorough encyclopedic discussion on that topic is beyond my scope. It is is something mentioned in the heading to these Talk Pages by Samsara, and needs urgent attention. Cruithne9 (talk) 16:37, 10 August 2016 (UTC)

Proposed partial revision of "The effect of sexual reproduction on species formation" subsection

The second paragraph of the subsection entitled "The effect of sexual reproduction on species formation" misrepresents Bernstein et al 's arguments, and quotes them out of context. Bernstein's main thesis is adequately summarized in the first paragraph.

The offending paragraph is also out of place in the subsection, being unrelated to the paragraph that precedes it, or the one that follows it.

I propose deleting it. Cruithne9 (talk) 08:07, 26 September 2016 (UTC)

If what you say is correct, then boldly go, at once. Chiswick Chap (talk) 08:34, 26 September 2016 (UTC)

OK Cruithne9 (talk) 09:47, 26 September 2016 (UTC)

Do it. This article needs some serious work. I plan to get to it eventually. I am currently working on the history of speciation, so I may be able to better contribute to the history section soon. At User:Azcolvin429/Speciation, I have created an outline of what I feel the article should be laid out like. Likely even less detailed as that. Speciation is an overarching term for a wide variety of phenomenon, so essentially, several chunks of the article are basically summaries of sub-articles (e.g. the primary modes). Andrew Z. Colvin • Talk 19:53, 30 September 2017 (UTC)