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

Re: Phylogeny of Maniraptora




James R. Cunningham <jrccea@bellsouth.net> wrote:

You're interpreting me correctly. There are times when being coplanar would be an advantage. There are other times when being actively non-coplanar might offer even more advantage. I gather from your
phrasing below that you accept hindlimb involvement in all wings associated with patagiums. If so, is that a functional requirement?

I was referring to the membrane (patagium) stretched between the forelimbs and hindlimbs of gliding mammals - colugos, "flying" squirrels, "flying" possums, and the like. The patagium links the forelimbs and hindlimbs in functional allegiance during gliding. _M. gui_ probably displayed a similar link.



Graydon <oak@uniserve.com> wrote:

You get something like flapping from the predatory stroke if you push a basal maniraptoran out of a tree; it may not do any good, but that's what its arms _do_ when trying to move rapidly, they're not the peculiar
wide-range-of-motion things people have got.

Sorry, I don't follow. Why would the maniraptoran flail its arms around in a predatory-stroke-like motion when falling from a tree?


Come to think of it, who pushed it out of the tree in the first place? What I'm getting at is, if a maniraptoran can get up a tree, it must have the ability to get down. Therefore, it may have evolved an apparatus that facilitated this route.

If it's a maniraptoran, it can flap. (maybe not *well*, but it can flap.)

But, *why* would it flap? You've explained the *how*, but not the *why* of the predatory stroke --> flight stroke pathway.





Tim

_________________________________________________________________
Add photos to your messages with MSN 8. Get 2 months FREE*. http://join.msn.com/?page=features/featuredemail