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Re: Question: Why did birds lose their teeth?
On Mar 11, 2014, at 1:44 AM, Martin Baeker <email@example.com> wrote:
> 1. Are bird beaks really weight saving compared to teeth?
As Jaime noted, beaks are often heavier.
> 2. If so, what might be an advantage of that? I think that the total
> weight loss is - as you write - small compared to body weight, but
> what about moment arms and the torque around the CoM during flight? Is
> that also small enough to be neglected?
Either way, the changes in the effective moment relative to the CoM (or perhaps
more notably, the Center of Lift) are negligible. One way of looking at this is
to consider how much change in wing sweep is required to accommodate the
altered moment if the skull is lightened by 1-3% or so (which is probably a
gross overestimate of the difference between teeth and beaks, but allows us to
be conservative). The change in sweep is so small that it’s practically not
even measurably (0.005 to .01 radians if one is generous with moment arms and
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