Come on, Tom....don't beat around the bush.  Tell us how you really feel
about cladistics.

Kurt

At 08:33 AM 5/23/00 -0400, you wrote:
>>Tom and David,
>>
>>According to an analysis of the data from 630 base pairs of DNA sequence
>>for the cytochrome oxidase I (COI) gene that is close.  The Unionoidea and
>>Unionidae are paraphyletic and it is hypothesized that the glochidium is
>>the ancestral unionoid larval type (the glochidium is not necessarily
>>paraphyletic however).  The Margaritiferidae, Mycetopodidae, Mutelidae, and
>>Hyriidae were all supported as monophyletic.  The topology of the tree is
>>thus: ((((Unionidae [excluding Coelatura], Margaritiferidae), Coelatura),
>>(Mutelidae, Mycetopodidae)), Hyriidae).  Neotrigonia was used as the
>>outgroup.
>
>Damn cladists! There's more to it than a single gene for God's sake! When
>they've looked at all the genes, get back to me. The trigonaceans may not
>even be ancestral to the unionaceans, despite "conventional wisdom." The
>Pachycardiids are probably the most closely related group, but they are all
>extinct. The study you mentioned found Neotrigonia to be the most similar
>among the groups used, but then they could only use living animals -
>pachycardiids would never even enter into their database. It would be like
>a DNA study of Nautiloids -- of course they would find the Coleoids the
>closest because they have no Ammonoids to compare. It's a shoe-horn
>approach to pop taxonomy. Damn cladists!
>
>
>
>
>
>*****************************************
> G Thomas Watters, PhD
> Ohio Biological Survey &
> Aquatic Ecology Laboratory
> Ohio State University
> 1315 Kinnear Road
> Columbus, OH 43212 USA
> v: 614-292-6170  f: 614-292-0181
>******************************************
>
>"The world is my oyster except for months with an 'R' in them" - Firesign
>Theater
>
>"Give a man a fish and you feed him for a day. Teach a man to fish and he
>has to buy a license" - GTW
>
>"Beliefs are more powerful than facts" - Duke Paulus Atreides
>