Re: birds/dino-birds with teeth

[John Conway <john_conway@mac.com>]

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/
>