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Re: Flight again (was Re: The Lizard of Oz)





David Marjanovic

IMHO the first is rather improbable because a jump from such a low height
lasts too short for selective pressure for steering structures to occur --

More improbable than underwater swimming?

It wasn't just for steering. It was for stability in landing - so the little predator didn't topple over when he hit the ground. That's one of the functions of modern bird wings.

A testable opinion of mine that has AFAIK not been tested: Downy feathers
are much too short and not stiff enough to exert measurable drag.

Why do tennis balls have fuzz?


Feathers for S excretion --> for insulation --> wings and maybe semilunate
carpal for brooding --> underwater flight, tail feathers for steering, wing
feathers slowly more asymmetrical --> flight in air? Lots of exaptations
here.

Sulfur exceretion? Underwater flight??? Those poor proavians - what they had to go through just to achieve powered flight. Even the Wright brothers never had it so bad.



Tim


------------------------------------------------------------

Timothy J. Williams

USDA/ARS Researcher
Agronomy Hall
Iowa State University
Ames IA 50014

Phone: 515 294 9233
Fax:   515 294 3163

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