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RE: Do we have dromaeosaurid evolution backward?
(plain text; sorry)
> Date: Thu, 25 Aug 2011 05:47:24 +0000
> From: keenir@hotmail.com
> Subject: RE: Do we have dromaeosaurid evolution backward?
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> > Date: Thu, 25 Aug 2011 15:28:23 +1000
> > From: tijawi@gmail.com
> > To: dinosaur@usc.edu
> > Subject: Re: Do we have dromaeosaurid evolution backward?
> >
> > David Marjanovic <david.marjanovic@gmx.at> wrote:
> > >> As I see it, one major problem with this idea is that if large,
> > >> pennaceous feathers originally evolved for aerodynamic purposes,
> > >> these feathers are unlikely to have arisen in "large" (2-4m long)
> > >> theropods that used their forelimbs for catching prey.
> > >
> > > I suppose that's where Hopp & Orsen (1998) come in.
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> > Using the forelimbs to help incubate eggs might explain the presence
> > of big pennaceous feathers. But it doesn't explain why those feathers
> > would be aerodynamic.
>
> Maybe they wouldn't be aerodynamic initially...but eventually.
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> its like with possums and squirrels: they may not all have gliding abilities,
> but most of them have figured out that if they jump off a branch, they can
> escape danger.
>