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Re: Campbell's even crazier than a MANIAC? (archeopteryx climbing)

David Marjanovic wrote:

<But then, no animal today has anything similar to a sickle claw.>

  That the claw function is being keyed in directly to that of predatory birds 
and cats, tells us that we are deliberately comparing the functionality between 
these groups.

<"The present is not the key to the past. The past is the key to the present, 
and to the future.">

  Exactly. Indeed, we must work with what has been known, and done, to develop 
what CAN be known, and be done. In this case, we have no clue what the past 
tells us with the claw function, since keratinous sheath covering the unguals 
of even extinct taxa is in agreement with that in extant bird taxa. This tells 
us the raptors being used for comparison are an excellent constraint. And they 
don't slice with the bulk of their ungual, just the tips. This is also how 
tigers disembowel prey.


Jaime A. Headden

"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)