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Re: Pterosaur wings and refs
"James R. Cunningham" wrote:
> David Peters and David Unwin wrote:
> >> Add to this Hazlehurst's (1991) discovery of a good correlation between
> >> fore and hind limb length in pterosaurs,
> > This is probably true because in a balanced standing bipedal pose the
> > distal metacarpus of nearly all pterosaurs will touch the ground, or at
> > least the ankle, by simple elbow extension (short-armed Austriadactylus
> > and Campylognathoides zitteli are the sole exceptions).
> But there are exceptions, implying non-bipedality in at least some
Or, as in these cases, quadrupedality requires abit of bending over. That's all.
Bipedality is a constant. I've done the reconstructions. They all balance over
the toes using the center of balance,
as in all flying animals, just aft of the humeral glenoid.
> In the animals I mess with, I've never seen much need for a
> balanced standing bipedal pose,
Of course not, Jim. You deal with Quetzalcoatlus. It spent all day standing on
all fours! And it was part of a clade
which did likewise.
> > I can send Internet links to mpg movies of same if interested.
> I'm interested, but my antequated computer craps out on mpegs. I'd like
> to have the links anyway.
The Irschick Lab >> http://www.tulane.edu/~irschick/
The Jayne Lab >> http://www.biology.uc.edu/faculty/jayne/bruce.htm
These will get you started.
> > quadrupedal plantigrady - as shown y thousands of pterosaur tracks,
?And one French quadrupedal digitigrade track with a posteriorly-directed
dorygnathid-like bent fifth toe. Then a big
gap and Rotodactylus in the Triassic, again with a posteriorly directed fifth
toe. Us digitigrade guys are
underrepresented because the filter-feeders and waders leaving all the tracks
are the flatfoots. The digitigrade
pterosaurs are of the soaring sort.
> Boy, you got that right. Particularly since it seems that the chord is
> actively variable,
Not variable. Sorry. The actinofibrils will not permit it. BTW, Just found out
the reference will be Historical
Biology 15, pp. 277-301.