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RE: origin of bats/reply 2 to TMK



--- On Wed, 6/25/08, Jeff Hecht <jeff@jeffhecht.com> wrote:

> Small maniraptors probably were both predators and prey,
> like housecats are predators on mice and lunch for coyotes
> (to borrow a convenient example from a seriously
> human-altered environment). A proto-flyer that dashed up a
> tree to escape a bigger and faster (but non-climbing)
> predator would have a big advantage in getting down if it
> had feathers to help it 'fall' in a more controlled
> manner. That could have evolved into swooping down on prey
> as well as simply getting down after escaping a predator.

Or to modify slightly, a perch predator could find that a fortuitous structure 
grants control (speed and/or direction) of downward leaps that is advantageous 
in BOTH acquiring prey and predator avoidance. Speed control, for example, 
allows a larger vertical range of perches to be utilized. No new ground here, 
of course...

> Animals can evolve some pretty odd behavior that works in
> their environment. Early in the 2nd episode of
> Attenborough's Birds (the one on flight), he shows
> shearwaters climbing a slanting tree, pumping their wings a
> bit like in Wing-assisted incline climbing, then flying off.
> According to Attenborough, they need to climb the tree to
> launch themselves into the air so they can fly, and they
> pick one tree that's easiest to climb. Could something
> like that have launched avian flight? 

I don't see why not.

Don