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Re: Arms into wings



I wrote:

<<However, the arms for wings would only have developed from shorter,
less "flight"-apparent limbs. Feathers, that's anyones guess, but they
possibly weren't around until the Mid-J, in their most basal form,
while "birds" like Archie were hopping from ______ to ______ with arms
that could, in nessecity, glide and propel it through the air. A
glinding stage preceeding true flight involves feathers. If so, then
feathers reach from (around) *Eoraptor* up to Archie in full flight
capability. We certainly don't assume skin-gliding as in mammals and
those kooky lizards and snakes would have been a part -- this requires
long arms, which according to all forms of phylogenetic reasoning,
would not have existed until that ancestral maniraptoran.>>

Larry Febo wrote:

<Who is "We"?>

  Sorry, I tried to edit that pronoun out of the text of the post, and
did so elsewhere, but missed this one. Should read "As far as my
studies show, _I and some others_ don't assume skin-gliding as in
mammals and those kooky lizards and snakes would have been a part --
this requires long arms, which according to all forms of phylogenetic
reasoning, would not have existed until that ancestral maniraptoran."

<What about my "Pterosaur to bird theory"?? Can`t it get ANY kind of
recognition around here???.....(sheesh!)
 
Pterosaurs had the long arms,...and the skin membranes...>

  Not to put your theory down, but the skin of avian arms is very
different from that of pterosaurs. My phrase was put in the context of
bird vs. mammalian gliding origins to flight and the extant gliding
and flying pattern in lepidosaurs and mammals. I did not consider the
pterosaurs, for one thing their different flying structures. There is
a greater corollary, for instance, between pterosaurs and bats. Finger
support of a wing membrane, or fingers at all. Pterosaurs developing
from short armed and long legged to the reverse, as in birds, should
be significant, since this is paralleled in birds, but the structure
of the ankles and arms are different in the evolutionary paths of both
when we get down to it; they went through similar solutions to the
same problems, but not identical solutions, and at the moment they
split, that was it. There is a line leading from small short armed
theropods to birds that is not matched in pterosaurs. All pterosaur
ansectors or possible ones had fully different morphology of the
shoulder, ankle, and pes than in birds and theropods, which are
closely matched.

  Additionally, pterosaurs possess not only a fourth "flight" digit,
but the structure of the "hand" is so highly different in even the
most primitive pterosaur (*Preondactylus*) that bird/pterosaur
homology of flight apparatus cannot be approached on similar grounds
except for the base dynamics that all flying vertebrates have (bats,
birds, pterosaurs, lemurs, fish, and squamates).

  That's all I will say on the matter. This applies to the homology of
flight, whichw as what I was talking about in the previous post, not
evolutionary relationships. That's your tackle to make, to use an
American football term.

==
- Greek proverb: "Knowledge is Inherent;
  Stupidity is Learned." -

Jaime A. Headden

Qilong, the website, at:
( http://members.tripod.com/~Qilong/ )
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