Re: Origin of feathers

[Dinogeorge <Dinogeorge@aol.com>]

In a message dated 98-04-23 00:51:51 EDT, Patrick.Norton@state.me.us writes:

<< I think the assumption in most energetics studies that protobirds ran   
 around trying to chase insects into the air is all wrong. A small   
 cursorial archosaur with undifferentiated feathers occupying a niche   
 similar to today's roadrunner would be a prime candidate for rapid   
 modification of wing and tail feathers---not for flight--but to obtain   
 aerodynamic advantages over prey during combat.  The hopping, bobbing,   
 weaving, jabbing strategy of the roadrunner requires all the architecture   
 of flight; yet they rarely fly. But the advantages those adaptations   
 provide in a predator/prey confrontation are enormous. If  you're trying   
 to get protobirds off the ground, don't think speed; think agility.  >>

I think what you are describing is an animal making the best use of equipment
it had inherited that had previously served a rather different function. Lots
of animals are quite agile and capable of overwhelming their prey without
needing feathers to do so. There is nothing compelling about this evolutionary
scenario. Indeed, the roadrunner could well be a bird in the process of losing
its flying ability, in which case the idea that flight arose via this pathway
would be exactly backward.