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Re: What is biomechanics? (or, The Truth About Flying Snakes - Was: Re: science and philosophy)



--- Colin McHenry <cmchenry@westserv.net.au> wrote:
> John Conway wrote -
> 
> >I'm sorry, I don't think there is "confusion" among cladists that you
> >refer to. In fact there is remarkable consistency - Dromaeosaurs and
> >Troodontids are the closest to birds.
> 
> Which just supports my point.  Dromaeosaurs and Troodontids make pretty poor
> precurosrs for a flying animal (from a biomechanical point of view), if you
> ask me.

Did he say "precursor"? No.

_Deinonychosauria_ (including _Dromaeosauridae_ and _Troodontidae_) is the
sister group to _Avialae_ (non Gauthier & de Queiroz), not an ancestral
assemblage. Deinonychosaurs aren't precursors to avians any more than
monotremes are precursors to therian mammals.

> Look, I know that this is the sort of statement that gets quoted back at you
> 20 years later to show just how bad humans are at making predictions, but;
> ....If I was charged with turning a theropod dinosaur into a bird then
> _Velociraptor_ or _Troodon_ are not the sort of animals I'd be starting off
> with.  I'd be looking for a small insectivorous thing scurrying around in
> the forests.

_Velociraptor_ and _Troodon_ are from the end of the Mesozoic -- they had
plenty of time to evolve from the eumaniraptoran ancestor of _Deinonychosauria_
and _Avialae_, which may well have been "a small insectivorous thing scurrying
around in the forests".


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=====> T. Michael Keesey <keesey@bigfoot.com>
=====> The Dinosauricon <http://dinosauricon.com>
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