[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Microraptor hanqingi, new species from China.

Am 22.05.2012 02:01, schrieb Tim Williams:

 evelyn sobielski <koreke77@yahoo.de> wrote:

> In and by itself, this is not necessarily absurd. Both trains of
> evidence may be correct without colliding - any arboreal form that
> should happen to descend from a cursorial-terrestrial form would
> necessarily evolve through a stage in which well-developed
> cursorial plesiomorphies coexist with crude arboreal apomorphies,
> and the material evidence *could* be interpreted thus in this
> case.

 Granted. But Gong &c do not interpret _Microraptor_ in this way.
 They regard _Microraptor_ as a sprawling quadruped incapable of
 terrestrial/bipedal locomotion. I find this very difficult to

They're probably using the interpretation that David Burnham presented at the SVP meeting of 2008. In their reconstruction, Burnham & coauthors actually took the femora out of the hip sockets, turned them by 90°, and let them clash with the hips so that there was no space left between the ilium and the trochanteric crest. They completely ignored the fact that the proximal side of the trochanteric crest is a muscle attachment site. <headdesk> There was so much embarrassed silence after that talk that I got to be the one who spoke out.

Yeah, well, once you somehow make the musculature disappear and have the femora in that position, it's difficult or impossible to put the cylindrical (not hemispherical or anything) femoral heads back into the hip sockets. That's meant by "obligate sprawling". It follows logically from painfully wrong premises.

 There were large columnar plants around, even if they were not true

There were perfectly cromulent trees around ever since the Devonian *Archaeopteris*. *Suminia* probably climbed in *Glossopteris*.