Re: Mei example

[Tim Williams <twilliams_alpha@hotmail.com>]

Gregory S. Paul wrote:

> Ergo the presence of well developed flight feathers and other avian 
> attributes such as the tucked in sleeping posture did not appear deep in 
> theropods and well before the advent of flight. Instead the supposed 
> exaptations for flight are adaptations for flight, latter retained or 
> modified for nonflight purposes by later avepectorans.

The 'neoflightless' Paulian hypothesis regards almost EVERY flight-related 
character in birds as originally evolving for powered flight.  I have deep 
reservations about this, because it requires that so many characters evolved 
specifically for flight that the Paulian hypothesis could be accused of 
bordering on teleological.  The strength of more exaptation-dependent 
hypotheses is that certain flight-related characters are held to have 
evolved originally for other purposes (especially predation), and later 
diverged toward an aerial function.  Thus, when the biped first ventured 
into the aerial realm (leaping, gliding, whetever), it had a number of 
pre-existing features that could be recruited for the purpose of aerial 
locomotion.  Th

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