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Re: Question: Why did birds lose their teeth?



On Wed, Mar 12th, 2014 at 3:16 PM, Tim Williams <tijawi@gmail.com> wrote:

> However, it's not immediately clear what the function of wing-claws
> actually was.  A function in climbing trees seems intuitively
> attractive, especially in basal birds that preferred not to (or were
> unable to) execute a ground-level take-off.  I'm not wholly convinced
> that climbing was the raison d'etre for the retention of wing-claws in
> many Mesozoic birds.

If the presence of manual claws wasn't actively maladaptive for the degree of 
flight capable at the 
time, there may simply have been no strong selective pressure to lose them. It 
may not have been 
until much later in avian evolution when flight capabilities were improved in 
general that 
suppressing the development of manual claws would have made a recognisable 
difference to flight 
efficiency, and thus became a trait that was positively selected for.

Sometimes traits don't need to have a practical function, as long as they're 
not actively 
disfunctional.

-- 
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Dann Pigdon
Spatial Data Analyst               Australian Dinosaurs
Melbourne, Australia               http://home.alphalink.com.au/~dannj
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