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Re: Archaeopteryx not the first bird, is the earliest known (powered) flying dinosaur
In a message dated 12/3/05 8:14:52 PM, email@example.com writes:
<< I would be careful about using the Thermopolis specimen as evidence for
a splaying posture; >>
So would I, I never claimed that any Archaeopteryx specimen favors a
sprawling posture, quite the opposite.
There is no Jehol dromaeosaur specimen, including Microraptor (I have the
same paper), that has the medially elongated, cylinderical femoral head seen in
standard theropods including Deinonychus. Draw the femoral heads in
antero-posterior view and compare them side by side rather than using general
made from isolated photos. That the leg winged dromaeosaurs have modified
femoral heads that in some ways resemble those of some pterosaurs suggests they
had evolved a different function, later lost in most secondarily flightless
examples. Which is why so many specimens are splayed out spread eagle style.
hip sockets and leg musculature would not have to be fully functional when
splayed out in flying dromaeosaurs because they were not using them for walking
or running (many joints are not in full articulation in animals when they are
not bearing full loads). Evolution is a make do sort of system, there being so
little intelligence involved.