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Re: Question: Why did birds lose their teeth?

And I add, now that I have accessed a fresh battery -- 

1) the reconstructions of toothy birds with wing claws that I have seen make it 
clear that the claws could reach the mouth, and thus could assist in clearing 
the obstructions inevitable when working with a small, tooth-infested intake 

2) it follows, as matter of selective logic, that if the claws disappeared as 
the wing was optimized aerodynamically, then then the teeth might follow -- 
flight being enough of an advantage in accessing prey (among other things) to 
counteract the occasional escape the lack of teeth might enable.

3) so! Does the record show a clear pattern of 'first go the claws, then go the 
teeth' in toothed birds? 

On Mon, Mar 10, 2014 9:14 PM EDT don ohmes wrote:

>Hence the inclusion of the term "small biped" -- there are multiple underlying 
>allometric principles involved.
>E.G. -- A large fish falls off a given spear more easily than a small fish 
>And a smooth solid food intake port is no guarantee of trouble-free dining -- 
>I observed a cattle egret impale a toad so enthusiastically that it ended up 
>half way to the base of the beak -- had the toad been larger, perhaps the 
>bird's vigorous headshakes could have transferred enough momentum to the toad 
>to overcome friction -- or, had the toad been smaller, the one foot per effort 
>the bird could use to push on the toad might have removed it. As it was, it 
>was in a bit of trouble, pun intended -- it could not open it's beak, and was 
>totally mobbed by it's flock-mates, who wished to steal the prize -- perhaps 
>50 birds, in all. 
>This concept is easily demonstrated with a steak and a kitchen knife -- 
>vigorous shaking might be required to remove a small piece of impaled meat, 
>while a heavier piece can be removed simply by pointing the knife downward.
>Also, the brute processing power attainable by terrestrial predators is simply 
>not possible for birds, as Pigdon explains in his initial post.
>Summing, small tubes are more easily clogged than large, and a very small 
>tooth is larger (relatively) to a sparrow's mouth than the daggers of T rex, 
>et al, are to it's massive head... 
>On Mon, Mar 10, 2014 8:17 PM EDT Mike Habib wrote:
>>On Mar 10, 2014, at 4:53 PM, Dann Pigdon <dannj@alphalink.com.au> wrote:
>> 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).
>>In fact, the vast majority of non-avian theropods could not reach their own 
>>mouths with their forelimbs, even those with relatively “robust” forelimbs, 
>>such as allosauroids (nor can they reach any area in front of themselves that 
>>they could see - which makes use in predation potentially cumbersome). 
>>Interestingly enough, among theropods, some living birds are among the 
>>derived taxa that can reach their mouths: with their hind limbs.