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Re: Mei example



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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