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Re: Hone and Benton 2007 (their second paper)

Secondly, and to get very hypothetical, let's say we had a bird with long legs, that can leap powerfully, but is incapable of a ground-to-air take-off. Let's also say that it's a rather poor flier that cannot fold its wings to the same extent as modern birds. The bird in question is something like, oh I dunno, _Archaeopteryx_. (I'm not saying that Archie was incapable of a ground-to-air take-off; but for the sake of argument I'll posit that it requires elevation in order to achieve flight speed). How do you think _Archaeopteryx_ would take off from a tree?

It is very hypothetical, but a fun question. I do note that is something of an odd hypothetical, because birds that can leap powerfully generally can use leaping launch. We'll assume for the moment that Archie's wing stroke capabilities are so poor that it cannot complete the leaping launch cycle (wherein the wings take over at the end of the leap), or something to that effect.

In any case, Archaeopteryx could launch from a tree just like most living arboreal birds, except it would not stay tucked as tightly during launch. That isn't a particularly problematic situation, and raptors (and corvids, I think) do not tuck on gravity-assisted launch as much as passerines. Most living passerines (large corvids excepted, as well as some others) are flap-bounding flyers, so a heavily tucked launch makes sense for them (it ends up being like a bound). Archaeopteryx was neither equipped physically, nor within the optimal size range, for flap-bounding. My best guess is that it would elevate the wings while leaving the branch, pushing off hard with the legs. The wings would then be depressed in an downstroke as Archie neared flight speed, which would only require a very brief descent. Archaeopteryx could then begin flapping normally, whatever that means for Archaeopteryx given it's deltoid-based upstroke and primitive shoulder.


--Mike H.