Re: vital effects and genetics

[c583scb@xxxxxxxxxxxxxxx (Dr Peter Roopnarine)]

>Thanks for your input.
>	I can't make much of a defense yet, but here's some intial thoughts.
>	Being a vertebrate paleontologist, I follow the rule that if they look
>similar, they lived similarly.  While this rule may not readily apply to such
>organisms as forams, diatoms, radiolara, and other marine microorganisms, there
>is the notion that the general shape of the test is somewhat adaptive,
>especially in forams.  As I said, if you have two sister species with a very
>similar morphology, then the difference with regard to isotopic controls
such as
>ecology and diet is minimal because they had nearly identicle ecological
niches.
>Which leaves the vital effect.
>	I'd like to see if there is a vital effect in vertebrate fossils, but
>current research focuses almost exlusively on forams.
>
>Eric Simpson
>Dept. of Geoscience
>Texas Tech University
>76653,1410@compuserve.com
>
>

Eric,
I probably didn't state this very clearly in my first comment on the vital
effects issue. Many exoskeleton bearing organisms are morphologically
sensitive to environment and age. Hence the reason for the success(?) of
factor analytical functions, and the entire justification for examining
ecophenotypy. Just because two forms are generally similar does not mean
that they had unimportant ecological or ontogenetic differences. If you are
approaching the vital effects question quantitatively, then be quantitative
all the way. Morphology must be described quantitatively, and not just by
eyeball. There is a lot of interesting material there!
Peter Roopnarine