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Re: The ground-nowhere hypothesis on the origin of bird flight
On Fri, Oct 9, 2009 at 2:46 AM, Tim Williams <tijawi@yahoo.com> wrote:
> At any given moment, the pro-avian can either be working with or against
> gravity, not both.
Or neither. Like insects flapping their wing to propel themselves over
water surface as in Thomas & Norberg 1996. (Well not that birds do
it.)
Or pro-avians could alternate not only along evolutionary history, but
in different situations in them lives: some birds dive flaping their
wings.
[]s,
Roberto Takata