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RE: Yet more on dinosaur quad climbers



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> Date: Fri, 12 Jul 2013 22:36:56 -0400
> On Fri, Jul 12, 2013 at 07:12:32PM -0700, Mike Habib wrote:
>> On Jul 12, 2013, at 6:58 PM, Ruben Safir <ruben@mrbrklyn.com> wrote:
>>> PS - the turtle problem is different. Accerting that the shell was
>>> not evolved because of its amour advantage would be the equivilent
>>> argument…
>>
>> Indeed. And in a similar sense, the early stages of shell expansion may not 
>> have been for armor, because the earliest changes in the turtle skeleton may 
>> not have conferred much protection. Just as for feathers, a functional shift 
>> likely occurred. Structures don't evolve for functions they'll have later.

>
> We are not talking about precursors and proto feathers, which were
> clearly NOT for flight. We are talking about wings and flight feather.

 and where did they come from?   if you say "they can't be feathers because 
they can't be used for flight", then you are contradicting yourself when you 
say "flight feathers can't be used for anything but flying."  (that's more of a 
feedback loop than something to determine what the earliest flight feathers 
were like)

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