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Re: pterosaur femora sprawl
----- Original Message -----
From: "David Peters" <firstname.lastname@example.org>
Sent: Wednesday, June 04, 2008 3:19 PM
Tested against _all_ prior contenders, civets/Ptilocercus/and a fossil
rostrum (can't recall name) come closest, so the uncertainty is reduced.
If you saw what I saw in the skeletons, you'd be on board.
But as long as it isn't published, what point is there in talking about it?
As long as we can't see the paper, we can't meaningfully talk about it.
Chalicotheres and anteaters, also knuckle walkers, may have just one day
decided to "save their nails." I don't know about how they changed
patterns. Were some small and arboreal?
Anteaters, yes: most are still small and arboreal.
Chalicotheres: no, never. And not all even walked on their knuckles. Some
were ordinary quadrupeds. Here it looks like the gait changed when the claws
became too long and curved.
Either way, it's a single, fairly simple shift on the tree,
so phylogenetic parsimony is probably not the best way to judge the
likelihood of the proposed launch system.
Never discount phylogenetics. It's the key you're trying to ignore because
it doesn't fit your paradigm.
Wow. That's strong stuff. That's an extraordinary claim, you know, of the
sort that requires extraordinary evidence.
Shake off all prejudices and let the phylogenetic evidence guide you. It's
real. It's not made up by engineers.
But it may be all wrong. The characters may be correlated, or fictitious, or
devoid of phylogenetic signal, or unordered when they shouldn't be, or
partitioned into states in an irreproducible way, or the matrix may be full
of typos, or who knows what. Nobody knows as long as it isn't published.
I brought up short-legged, long-handed Nyctosaurus because it would seem
it was operating with oversize "crutches" that would not have been able to
be angled at a posterior vector for a quad launch that sent the pterosaur
If I've understood the quadrupedal-launching scenario, the forward thrust is
provided by the hindlimbs, and the forelimbs just push the animal up. Right?
Comparative number of silver bullets, you mean.