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Re: Question: Why did birds lose their teeth?

Seemz right to me, at as far as selective logic goes -- and it raises the 
question -- might a claw of the right size and location relative to the wing be 
adaptive to flight? 

Given a flapping flier, it is easy to imagine that a claw might create small 
vortexes under the wing (upstroke), or over it (downstroke).

Also: The list of species in which "vestigial" claws are found is not 
negligible -- but do domesticated birds count, unless claws are common in the 
wild-type rootstock? 

On Wed, Mar 12, 2014 5:48 PM EDT Dann Pigdon wrote:

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