Re: vital effects and genetics

[bivalve@xxxxxxxxxxxxx (David Campbell)]

One example of a chemical difference between species (which has only brief
mention in published literature) occurs in Pliocene Crepidula (slipper
snails) from South Carolina.  One of two morphologically similar species
usually has an iron stain in the middle; the other never does.
Some isotopic studies on dinosaur bones have suggested an intraorganismal
vital effect-bones nearer the middle of the body had a more constant,
warmer temperature.  I don't know of any interspecific differences among
morphologically similar taxa, though.

David Campbell   "old seashells"
Department of Geology
CB 3315 Mitchell Hall
University of North Carolina at Chapel Hill
Chapel Hill NC 27599-3315
bivalve@email.unc.edu