[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Question: Why did birds lose their teeth?




 Interesting question, and I hadn't thought to ask it -- it certainly wasn't 
flight-related, though ;).

Accepting for the moment that a viable explanation for tooth loss in birds must 
also explain turtles -- are clawless, but toothed turtles known? Is a pattern 
of first claw loss, then tooth loss seen in turtles? Perhaps "modern" land 
turtles are secondarily clawed? 


------------------------------
On Tue, Mar 11, 2014 2:08 AM EDT Dr Ronald Orenstein wrote:

>In which case, why did turtles lose their teeth?
>
>Ronald Orenstein 
>1825 Shady Creek Court
>Mississauga, ON
>Canada L5L 3W2
>ronorenstein.blogspot.com
>
>> On Mar 11, 2014, at 7:53 AM, Dann Pigdon <dannj@alphalink.com.au> wrote:
>> 
>> 
>> On Tue, Mar 11th, 2014 at 9:41 AM, don ohmes <d_ohmes@yahoo.com> wrote:
>> 
>> 
>> I do not claim this is testable (I have thought of one possible way, I will 
>> mention it later),
>> but a plausible selective path to tooth loss in birds is clear. 
>> 
>> Think about this next time you are flossing -- small bipeds that cannot use 
>> their hands to clear
>> stuck/snagged material from their mouths have a problem -- if they are 
>> volant, the problem is
>> exacerbated. 
>> 
>> Fully optimizing wings (in birds) for flight logically and apparently 
>> demands losing the claws --
>> and a toothy bird is just that more likely to die from something a little 
>> too big to swallow, not
>> to mention catching something too large in the first place! 
>> 
>> Perhaps there is a clear pattern in the data of 'first go the claws, then 
>> the teeth'?
>> 
>> How often to extant non-volant reptiles try to clear their mouths with their 
>> limbs?. I imagine it'd be 
>> impossible for crocodilians, not to mention potentially limb-shredding for 
>> monitor lizards. 
>> 
>> Many non-volant toothed theropods also had long necks and short forelimbs, 
>> making any sort of 
>> grooming of the mouth via the forelimbs unlikely (tyrannosaurs and 
>> carnotaurus are obvious 
>> examples).
>> 
>> -- 
>> _____________________________________________________________
>> 
>> Dann Pigdon
>> Spatial Data Analyst               Australian Dinosaurs
>> Melbourne, Australia               http://home.alphalink.com.au/~dannj
>> _____________________________________________________________
>>