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Re: Question: Why did birds lose their teeth?




Naish's blog makes no mention of possible aerodynamic effects that I saw,  and 
(although it has been years since I read Rand) I am fairly certain he does not 
either.

Although I will be unsurprised if "no aerodynamic consequence" proves to be the 
correct case, thr reason I mentioned it is that such structures are quite 
common on flywings (phorids and fruitflies) -- and likely are aerodynamically 
functional -- albeit at much lower Reynold's number.

Nor do any texts in my ken reference what seems obvious -- domesticated birds 
are of little account, from the perspective of natural selection...

...to answer my own, largely rhetorical, 2nd question.

------------------------------
On Wed, Mar 12, 2014 10:42 PM EDT Dann Pigdon wrote:

>
>On Thu, Mar 13th, 2014 at 12:11 PM, don ohmes <d_ohmes@yahoo.com> wrote:
>
>> 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? 
>
>Most of the vestigial claws I've seen on bird wings are so small they'd be 
>completely lost beneath 
>the feathers of the live bird, so would probably have no aerodynamic 
>consequences at all. That 
>may well be why they haven't been lost completely.
>
>The wing claws of emus and ostriches are anything but vestigial. Ratites don't 
>have any flight 
>requirements though, so there'd be no selective pressure to reduce their 
>claws. They actually look 
>like quite functional talons, so there may even be positive selection to keep 
>them (whatever it 
>might be).
>
>Darren Naish has some great posts on his blog on the subject:
>
>http://scienceblogs.com/tetrapodzoology/2010/06/30/clubs-spurs-spikes-and-claws
>http://scienceblogs.com/tetrapodzoology/2010/07/14/spurs-blades-jacanas-lapwings
>
>-- 
>_____________________________________________________________
>
>Dann Pigdon
>Spatial Data Analyst               Australian Dinosaurs
>Melbourne, Australia               http://home.alphalink.com.au/~dannj
>_____________________________________________________________
>