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Re: Did dinosaur wings evolve for breeding display?/Longisquama
David Peters wrote:
Never forget Dial's studies with young birds with small wings.
The wings of juvenile chukars using WAIR are still larger than the
forelimbs of Longisquama. There are a host of other reasons that
Longisquama would not be a good WAIR candidate, as well. There is
very little real evidence for even partial volancy in Longisquama at
this time, but that does not mean it cannot have volant relatives.
Also the previews to a new Disney movie, Earth, show a duckling
'parachuting' to the leaf litter. Wing length is not as important as
Wood ducks don't really parachute, so much as simply fall. Their
terminal velocity is quite low, and they fall onto leaf litter, so
there is little need to speed reduction. The falling ducklings do
wave the forelimbs, and maybe produce some useful drag that way, but
it is more likely that this is a reflex action related to an attempt
to keep balance.
Especially when you consider Longi's cousin: Sharovipteryx. Don't
follow your preconconceptions. Follow the fossils. Flapping doesn't
necessarily mean flying, either. Birds flap long before they fly
Yes, but for most species this is probably primarily a method of
exercising the wings (which, in part, helps to stimulate strengthening
of the forelimb skeleton).
Michael Habib, M.S.
Center for Functional Anatomy and Evolution
Johns Hopkins School of Medicine
1830 E. Monument Street
Baltimore, MD 21205