Re: FLIGHT VERSUS BROODING

[Betty Cunningham <bettyc@flyinggoat.com>]

Mexican free-tailed bats will fly up to two miles high to feed or to
catch tail-winds that carry them at speeds of more than 60 miles per
hour. I somehow don't think high altitude is restricted to birds with
air sacs.

-Betty Cunningham

Richard Swigart wrote:
> 
> -----Original Message-----
> From: Jonathan R. Wagner <znc14@TTACS.TTU.EDU>
> >>so they do not need large sterna. Increased attachment area for
> >>flight muscles, and increased ventilation of air-sacs needed to sustain
> >>flight, are the best explanations for the large sterna of these theropods.
 
>     Flight is not restricted to birds alone.  Bats and pterosaurs managed
> flight quite well without the increased attachment area for flight muscles,
> and air-sacs needed for sustained flight.
>     In light of this, I would suggest that air-sacs developed for another
> reason -- high altitude perhaps.  I don't think either are needed for
> sustained flight, or someone needs to tell the bats to quit migrating.
>