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

["Tim Williams" <twilliams_alpha@hotmail.com>]

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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