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Re: flight stroke (pretty short)

----- Original Message -----
From: "Waylon Rowley" <whte_rbt_obj@yahoo.com>
Sent: Friday, May 10, 2002 4:12 AM

[about all the paragraphs that I snip without answering... that means that
either I agree, consider the discussion finished and am too lazy to say so,
or that I find nothing to answer. You choose. :-) ]

> > Hm... I think this implies that gliders would just
> > as quickly be outcompeted by incipient flappers.
> Pterosaurs had begun to decline by the LK, correct?

Maybe... but they weren't gliders or incipient flappers, if you mean that.
(Maybe I can blame pretty much on the Cenomanian-Turonian mass extinction.
Just guessing. :o) )

> > Might still provide a selectionary advantage if it
> > tumbled back far enough away :-)
> Yes, I suppose it would if there were a reason to fly
> further.

Ebel has supplied two possible reasons... flight (pun inevitable in
English), and the fact that fish can be seen more easily from above than
from in the water.

> > I just wonder what exactly the disadvantage of a
> > long tail is.
> It may just be an indicator of how much time an animal
> spends in the air.

Good idea.

> I still like the
> idea of flapping evolving from quadrupedal climbers
> reaching for branches. I don't see any problems with
> the hypothesis. Really, how could you shoot it down?

For bats? Not at all. For birds? By showing that their ancestors can't have
been climbers. Will probably require a few more fossils (or at least
descriptions) for a definite answer, but at the moment I do think they
weren't climbers. :-) (Remember that SVP abstract on chicken embryology --
the hallux is first in a normal theropodan position and descends and reverts