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Re: Campbell's even crazier than a MANIAC? (archeopteryx climbing)
--- On Thu, 9/25/08, Tim Williams <email@example.com> wrote:
> > Since many improvements in parachuting and/or gliding
> ability don't lead
> > toward the direction of powered flight, doesn't
> that create problems for
> > your scenario?
> If gliding did lead to flight in the ancestry of bats,
> it's clear that exceptional circumstances were involved.
> So much for this route being "easy". ;-)
It is not too surprising that there are no gliders currently making the
transition to powered flight, considering the fact that they would have to
invade niches occupied by birds and/or bats as they did so. Seems a lot to
Competitive exclusion logically explains the paucity of gliding predators, too.
And that in turn explains why most extant gliders are 'just moving from
BTW, are there ANY cursorial vertebrates currently "moving in the direction of