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Re: Question: Why did birds lose their teeth?
On Tue, Mar 11th, 2014 at 1:16 AM, Martin Baeker <firstname.lastname@example.org> wrote:
> I once learned that losing teeth was a weight-saving measure and thus
> a flight adaptation. There is this reference stating this as a possibility
> However, I seem to remember that there was some study showing that
> birds actually do not lose signifcant weight by replacing teeth with
> beaks - if anybody has a reference on this, I'd be grateful.
There may not have been a single source of selective pressure for loss of
teeth. A whole lot of
separate minor advantages may well have added up.
Constantly shedding and replacing teeth might have been an expensive use of
instance, that could otherwise be used to stengthen bones against the rigours
of flight, or for the
production of hard-shelled eggs that were larger relative to body weight than
those of non-volant
The weight of the teeth themselves may not have been the only weight-saving
The lack of teeth might have allowed the jaw bones to become more slender,
making it possible to
make do with a much more light-weight skull. The jaw bones of tooth-bearing
generally the toughest bones in the body (which is why jaw bones are so common
in the fossil
record). In some modern birds, the mandibles are little more than whispy
splints of bone once the
beak has been removed.
Spatial Data Analyst Australian Dinosaurs
Melbourne, Australia http://home.alphalink.com.au/~dannj