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Re: CNN: how first birds flew



Jim,
    Thanks for the prior discussion. I know the argument I raised isn't 
original,
but it interests me as something that is calculable and may help focus
research.
Two points:
    1. Even small wind-catchers on the ends of extended arms can provide
a good deal of torque at the body center of mass, so it does seem
reasonable to imagine that the earliest protowings served as "control surfaces"
for fast runners before they found use as thrusters.
    2. Watching predator-prey chase scenes in wildlife movies, it
often seems that maneuverability is as important as speed in getting
dinner or avoiding becoming dinner.

Questions: I don't have any ostrich movies handy to look at. Do ratite
birds flap their wings when they run?

James R. Cunningham wrote:

> > >My (jrc) personal opinion is that earlier birds used their wingtip and 
> > >tail tip
> > >tufts to increase their manueverability but not their running speed.