Re: Origin of feathers

["Jonathan" <spockjr@email.msn.com>]

->Norton, Patrick wrote:
>
>> >But if you state that pre-feathers appeared >for< insulation, you imply
>> that homeothermy was already present >before< the pre-feathers appeared.

An interesting idea proposed last weekend at Dinofest by
Mark Orsen is that feathers may have evolved for the purpose
of brooding early on in the history of theropods.
He used Oviraptor as an example.  If you've seen the most
recent fossil of O. sitting on it's nest, you can see it is trying
to cover its eggs to protect them from the presumably scorching
heat of the Mongolian desert.  But, without feathers, it would have
only covered some of the eggs.  Orsen took the picture of the
Oviraptor fossil and superimposed primary feathers onto its
forearm and lo and behold they would have perfectly covered
the eggs.  Makes a lot of sense, perhaps more so than any of
the other theories.   It would have offered a great selective advantage
to those animals which could protect their eggs and subsequently
their young after hatching.  Then feathers could have been exapted
for flight.

Jonathan

Spockjr@msn.com