Re: The Return of More New Papers

["T. Michael Keesey" <keesey@gmail.com>]

On 4/16/07, David Marjanovic <david.marjanovic@gmx.at> wrote:
> > Ichnological evidence confirms that the theropod hand
> > also comprises digits 2-3-4.
>
> Except that not one of those hand prints is from a theropod. How do I know?
> Because to this day no known theropod has been able to pronate its hands
> enough to make non-sprawling quadrupedal walking possible.

To be fair, it's quite possible (likely, even) that the earliest
theropods were only facultatively bipedal. _Theropoda_ is a
branch-based taxon, so its earliest members would be practically
indistiniguishable from the earliest members of the sister group
(_Sauropodomorpha_) or the latest members of the stem lineage
(non-eusaurischian _Saurischia_). Put another way, the inability to
pronate does not define _Theropoda_, even though it is evidenced in
all known members.

But I agree--it seems that the trackways are more likely something else.

--
Mike Keesey