Re: Campbell's even crazier than a MANIAC? (archeopteryx climbing)

[David Marjanovic <david.marjanovic@gmx.at>]

----- Original Message ----- 
From: "Erik Boehm" <erikboehm07@yahoo.com>
Sent: Saturday, September 27, 2008 1:32 AM

> > I don't see how this follows.
>
> If it can fly... it can glide - aside from direct thrust flight (rockets, 
> VToL jets).

Agreed.

> I don't think the ability to fly powered could have possibly come before 
> the *ability* to glide (that isn't to say they would routinely stop 
> flapping midflight)

I still don't see how this follows. Especially when I consider the lack of 
tertials in Archie.

> > > I think its highly likely powered flight did not come
> > before soaring.
> >
> > The fossil record points in the opposite direction: the
> > bats still haven't got the idea of soaring, and the birds
> > seem to only have evolved it after the Mesozoic was
> > over. Even the pterosaurs started with small forms that
> > didn't have particularly long wings.
>
> Well, we don't know if bats ever did soar at any point in the past, and I 
> am specifically implying ridge soaring, not using thermals.

"Know" is too strong a word, but there's no evidence any bat ever soared, 
neither direct nor phylogenetic nor even geographic. Ockham's Razor thus 
argues against it.

And how actually would soaring evolve into flapping?

> [...] I still think ridge soaring was probably one of the first niches a 
> ptero or dinobird occupied once it had wings giving it any kind of gliding 
> ability, before the wings and muscles were large enough for powered 
> flight.

The wings, at least, may well have become large enough for flight long 
before flight started. That's because the wing feathers of birds may well 
have evolved for brooding and/or display rather than any aerodynamic 
function.