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Re: Family Nemegtosauridae
In a message dated 4/9/99 2:45:12 AM EST, A.Yates@zoo.latrobe.edu.au writes:
<< It has almost certainly
evolved on multiple independant occasions. There are at least three,
probably six such instances in sauropod phylogeny. They include the
euhelopodids (which becomes two instances if the family is not monophyletic
and Euhelopus is a somphospondyl), advanced diplodocimorphs and
Camarasaurus. Phuwiangosaurus becomes the fifth if it is correctly placed as
a basal titanosaur and Op. is of cousre the sixth if it is a derived
titanosaurid. >>
Try to imagine sauropod phylogeny with neural-spine bifurcation as occurring
>just once<, but in several stages, starting with the anterior dorsals and
posterior cervicals, and then progressing up the neck and down the back. Much
more straightforward.