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Re: Question: Why did birds lose their teeth?
Martin (and list):
I am having trouble finding that specific reference, as well, though a bit of
quick math shows that tooth loss in birds can’t remove significant weight
because the entire hard tissue skeletal system (teeth included) only accounts
for about 25-35% of total body mass, of which half is water. By way of example,
the total dry mass of both humeri in a mid-sized bird (390-500 gram range)
ranges from about 0.7% to 1.2% of total mass. The teeth would presumably make
up less mass than that of both entire humeri. The potential loss of mass from
losing teeth is dwarfed by the body mass changes from simply burning fat and
muscle in flight. During long migrations, some birds lose 50% of their body
mass. Under those conditions, the lost of teeth is practically rounding error.
—Mike
Michael Habib
Assistant Professor of Cell and Neurobiology
Keck School of Medicine of USC
University of Southern California
Bishop Research Building; Room 403
1333 San Pablo Street, Los Angeles 90089-9112
Research Associate, Dinosaur Institute
Natural History Museum of Los Angeles County
900 Exposition Blvd, Los Angeles, CA 90007
https://plus.google.com/+MichaelHabib/about
biologyinmotion@gmail.com
(443) 280-0181
On Mar 10, 2014, at 7:16 AM, Martin Baeker <martin.baeker@tu-bs.de> wrote:
> Dear all,
>
> 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
> http://www.newscientist.com/article/dn18248-early-birds-may-have-dropped-teeth-to-get-airborne.html#.Ux3HhdsjulM
>
> 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.
>
> Thanks a lot,
>
> Martin.
>
> Priv.-Doz. Dr. Martin Bäker
> Institut für Werkstoffe
> Technische Universität Braunschweig
> Langer Kamp 8
> 38106 Braunschweig
> Germany
> Tel.: 00-49-531-391-3065 <=== NEW phone number!
> Fax 00-49-531-391-3058
> e-mail <martin.baeker@tu-bs.de>
>
> http://www.tu-braunschweig.de/ifw/institut/mitarbeiter/roesler1
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