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Re: Greg Paul is right (again); or "Archie's not a birdy"
David Marjanovic <firstname.lastname@example.org> wrote:
> Undulating flight means alternating between fluttering and a purely
> ballistic phase with completely folded wings. Lots of small birds fly that
> way. No gliding in there.
No, you're thinking of bounding flight. Undulating flight has a glide
phase. Check out Rayner, JVM (1985). "Bounding and undulating flight
in birds" J. Theor. Biol. 117: 47-77. "In undulating flight.... the
animal glides during the rest phase, so that speed is approximately
constant and the flapping phase serves primarily to gain height."
> Too bad that *Volaticotherium* destroys it.
_Volaticotherium_ was certainly an insectivore. But although we have
no evidence that _Volaticotherium_ gave rise to flapping fliers, we
cannot dismiss the possibility that its descendents employed