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Re: Mei example



Greg Paul (GSP1954@aol.com) writes:

<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. Why researchers
continue to insist that Archaeopteryx and birds form a clade above
deinonychosaurs, oviraptorosaurs etc escapes me.>

  The "tucked-in" physical posture apparently preceeded theropods in the
chart of evolution, as it was present in *Stenopelyx,* *Psittacosaurus,*
and the "apparently" non-dinosaurian *Procompsognathus* (see new SVP
abstract that suggest this [certainly plausible] phylogenetic argument);
also note the famous *Corythosaurus* mummy shows a leg posture consistent
with "tucking," even though it's on it's side. Add to that similar
adaptations for tucking the legs and evidence for incipient or latent
arm-folding mechanisms in decidedly non-flying animals whose direct
ancestors NOT bearing these features were also flightless, suggests that
this posture had _nothing_ to do with flight. Maybe it was about leaping
from trees. Maybe it minimized body surface exposure during brooding or
hibernation. Maybe it was about being a predator and the need for a "snap"
reflex to engage prey.

  There are a host of theories, and neoflightlessness is but one and still
fails the parsimony argument (largely because many of the most vocal
opponents of parsimony -- several of whom deny the dinosaur-bird link --
think [without proof] that some evidence is "better" than other evidence).
More on that when Mickey replies shortly.

  As for sleeping, rehashing this a tad: What proof shows me that *Mei*
was sleeping in this posture, versus hunkering down during a
volcanoclastic explosion? I certainly wouldn't be able to sleep during a
volcanic outpouring next door (I live 20 miles away from the re-awakening
Mount St. Helens, imagine). Sleeping, methinks, is a subjective
observation of the posture, but so is protecting your face and attempting
to breath better.

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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


                
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