Posted by:
CKing
at Mon Jul 28 17:06:15 2008 [ Email Message ] [ Show All Posts by CKing ]
>>Hello great and powerful Cking. We've chatted before...
>>
>>I do have a question as a student of evolution...
>>
>>If slowiskii is more red because of a more wooded and coastal habitat...and emoryi are not due to their habitat selection...would this not be indicative of speciation? If each were to persist in the same habitat that they do now (isolated from one another), wouldn't each of their trajectories make them seperate species eventually? Thanks.>>
Within any one species, there are different ecomorphs. It is true that exploitation of a new ecosystem has led to morphological changes, and in some cases even to the appearance of new species. The job of a scientist is not to identify future evolutionary trajectories or trends, because scientists are not in the business of fortune telling. We have to decide instead whether the ecomorphs that exist today represent a single wide ranging species or two or more different species. That to a large degree will depend on data which show whether two populations that are in contact will or will not interbreed freely. If two populations are allopatric, then the job of determining conspecificity becomes more difficult.
What I was objecting to is the delimitation of mtDNA clades as "species." mtDNA cannot be used to ascertain morphology or the ability to interbreed, since mtDNA does not code for morphology. Besides, the mtDNA data shows that Elaphe guttata is a clade, not a polyphyletic assemblage. So, as far as the available mtDNA data show, E. guttata is but a single wide ranging species. If other sorts of data (e.g. number of chromosomes) shows that there is a good likelihood that the populations currently grouped under E. guttata cannot be conspecific, then we may have to divide it up into separate different species.
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RE: Where does emoryi stop and slowinski - CKing, Mon Jul 28 17:06:15 2008
