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Darren Naish wrote:

> With re to the 'feathers evolved as insulators' thread..
> Feathers are the most complex structure to have grown out of vertebrate skin
> _ever_. To argue that this structure _just happens_ to have been, later on,
> usefully exapted for flight is illogical. The only way to explain the initial
> appearance of feathers is to say that they evolved for aerodynamic purposes.

It would seem that the solution to this should lie in the structures
of the feathers themselves.

Are body feathers modified flight feathers, or are flight feathers
modified body feathers?  

Should body feathers come first, then almost certainly endothermy
preceeded flight (a nice pro-warm dino position).  Should flight
feathers be the base position, it might weaken the case for
warm-bloodedness among dinosaurs and proto-birds.  Even in a very
equitable climate, warm-blooded creatures small enough to fly on a 
feathered wing would have been subject to heat loss.

Birds are masters of erasing their origins.  No other vertebrates
have been so efficient at scouring their genes of all ancestral
traces.  But surely there must remain clues in feature structure to
indicate which type of feather is the Father of Fathers.

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