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RE: vaulting pterosaur launch, questions
Michael Habib wrote:
> True; it has been assumed as the "basal" launch style by many workers.
> I'm not sure why that is, other than perhaps tradition built on some
I'm sure he wasn't the first, but the 'running take-off' was discussed by
Speakman (1993). It's based on the relatively puny pectoral muscle mass of
_Archaeopteryx_. The argument runs that having flight muscle mass at or below
16% of total body mass renders the bird incapable of a stationary take-off.
_Archaeopteryx_'s is estimated at 9% - so it's well below the cut-off. Grebes
are said to have a flight muscle mass below 16%, which is why they require a
requiring a "taxiing" run in order to become airborne. Speakman doesn't
necessarily endorse this line of reasoning; and the grebe example comes from
> Birds also don't receive
> much limb excursion from the femur any longer, so shortness carries
> limited cost (stride length is largely unaffected).
Yes. The kinetics do change, especially during rapid progression - leading to
what's been called "Groucho running". :-)
Marden, J. H. (1987). Maximum lift production during take-off in flying
animals. J. Exp. Biol. 130: 235-258.
Speakman, J.R. (1993). Flight capabilities in _Archaeopteryx_. Evolution 47:
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