Talk:Divergent evolution

From Wikipedia, the free encyclopedia

	This article is part of WikiProject Evolutionary biology, an attempt at building a useful set of articles on evolutionary biology and its associated subfields such as population genetics, quantitative genetics, molecular evolution, phylogenetics, evolutionary developmental biology. It is distinct from the WikiProject Tree of Life in that it attempts to cover patterns, process and theory rather than systematics and taxonomy. If you would like to participate, there are some suggestions on this page (see also Wikipedia:Contributing FAQ for more information) or visit WikiProject Evolutionary biology.
B	rated as B-Class on the assessment scale
Mid	rated as mid-importance on the assessment scale

Does anyone know if this is synonymous with adaptive radiation? Might need a redirect if so... --postglock 06:14, 21 Jun 2005 (UTC)

I don't think it's synonomous, but a new word used with specific reference to molecular evolution (I think). I spent a while checking this line by tonight, and there are a lot of errors here. For example the divergence of vertebrate limbs is certainly an example of adaptive radiation. "Divergent evolution" is not a term I've seen used before with reference to species. As far as I can tell it's a neologism from the molecular community that refers specifically to DNA or amino acid sequences, rather than to whole organisms or even phenotypic characters such as limbs. "Speciation" and "adaptive radiation" cover the phenomenon of phenotypic divergence quite well and have a long history.

The distinction between convergent evolution and parallel evolution is badly covered here and should be omitted. D. J. Futuma describes the difference clearly in the second edition of his text on evolutionary biology. That would be a good source for a better discussion in the article on parallel evolution.

Some miscellaneous comments: "Divergent evolution occurs when two or more biological characteristics have a common evolutionary origin but have diverged over evolutionary time. This is also known as adaption or adaptive evolution."

Why "two or more"? If it's only one characteristic, why would it have a different name?

I believe the following is the meat of this definition and most of the rest of the article might be deleted. I recommend editing this passage for clarity. For example, omitting "two or more" might be helpful, since the important point is that they are homologous genes.

"Alternatively, "divergent evolution" can be applied to molecular biology characteristics. This could apply to a pathway in two or more organisms or cell types, for example. This can apply to genes and proteins, such as nucleotide sequences or protein sequences that derive from two or more homologous genes. Both orthologous genes (resulting from a speciation event) and paralogous genes (resulting from gene duplication within a population) can be said to display divergent evolution. Because of the latter, it is possible for divergent evolution to occur between two genes within a species."

"The usage of this term and other related terms can vary slightly from one researchers to the next."

This could be because some of the researchers are confused. I gather "Divergent evolution" is a neologism, apparently defined in opposition to "convergent evolution." I looked in the indices of five books about evolution (by Futuyma, Ridley, Mayr, Dobzhansky, and Freeman, 2/e) and did not find the term "divergent evolution" in any of them.

I recommend a pretty thorough revision of this article. I would omit the organismal examples and focus on how the term is used by the molecular community. Eperotao 02:54, 13 November 2006 (UTC)

This article is confusing. I suggest that it be defined at the beginning of the article. Right now, it just starts as if it had already been talking about divergent evolution.66.255.194.1 (talk) 01:28, 3 May 2008 (UTC)