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Re: birds/dino-birds with teeth



On Friday, May 3, 2002, at 02:22 AM, Jaime A. Headden wrote:

John Conway (john_conway@mac.com) wrote:

<How about aerodynamic reasons? Having no lips, bird teeth would (very
slightly) increase drag. This might go for toothless pterosaurs too. :-)>

This would have required the presence of lips or such integumental
tissue around the mouth to begin with, which is a debated issue. Similar
to this, though, is that many birds with flaps of skin around the head or
neck tend to be relatively grounded or flightless, including cassowaries,
turkeys, and chickens. Some of the fastest or "best" fliers, such as the
swift (*Apus*) or the peregrine (*Falco*) have very shortened profiles, a
"retracted" head, and specifically a very short and small beak and hence a
small profile.

and On Friday, May 3, 2002, at 03:50 AM, Larry Febo wrote:

.....maybe. Perhaps they were adapting to "prying-out" insects from crevices
in the bark???

Actually, my idea that birds lost their teeth for aerodynamic reasons was a joke. The VERY slight savings in weight or improvement in aerodynamics resulting from the loss of teeth would hardy outweigh any functional advantage in having them.


The chances that birds lost their teeth for weight saving or aerodynamics is very low indeed. Only after the teeth had lost their function in feeding were birds free to dispense with them. So the primary cause had to be feeding habits.


John Conway, Palaeoartist

"All art is quite useless." - Oscar Wilde

Protosite: http://homepage.mac.com/john_conway/