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re:?flightless pteros on islands



Rob Gay wrote:

On the subject of flightless pterosaurs - considering the tendency for
birds
to lose flight on islands, I would be surprised if flightless pterosaurs

didn't exist. However, the chances of finding one is very unlikely
(IMHO),
considering they would most likely be found on "smaller" islands - not
exactly prominent in the geologic record. It was once suggested to me
that
the coast of California, with its accreted terranes, would be the place
to
look.
Peace,
Rob


>>>>
Currently the pteros with the shortest wings (wing/torso ratios under
3.8) are the ctenochasmatids (sans Pterodaustro), but they have an
elongated torso. Also on the list is the grade Sordes + Scaphognathus +
Nos. 6, 9 and 23 (of Wellnhofer 1970) a series related cladistically and
notable for their phylogenetically decreasing size. However all have
wings that, when quadrupedal extend as high as, or higher than the
skull.

On the other hand, the azhdarchids have a longer wing/torso ratio, but
their wings decrease phylogentically so by the time you get to the big
azhdarcids, the wing tips barely clear the top of the back when folded
and walking quadrupedally. They make up for that decrease with elongated
metacarpals.

Finally, as Greg Paul put it in DA, if you just got your wings, you're
more likely to lose them again, so perhaps we should be looking for
flightless pterosaurs in the Triassic.

Not sure which are the better set of candidates for flightlessness.
Perhaps you all have some ideas?

I think pteros were using their wings  for display, both as infants
begging for food and as sexually active adults. Any pterosaur with short
wings would have been relegated to smoking outside of the gym while all
the others were dancing to the beat.

David Peters
St. Louis