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Re: Ah ha! That's where therizinosaurs came from
On Mon, Aug 15, 2011 at 11:01 AM, <GSP1954@aol.com> wrote:
>> In a message dated 8/15/11 10:44:05 AM, firstname.lastname@example.org writes:
>> On Sun, Aug 14, 2011 at 9:42 PM, Tim Williams <email@example.com> wrote:
>>> The biggest problem with GSP's "neoflightless" hypothesis is this: It
>>> proposes that tree-dwelling theropods had plenty of time to evolve an
>>> extensive list of "flight-related" characters (advanced
>>> scapula-coracoid morphology; foldable forelimbs; shorter and distally
>>> stiffened tails; large contour feathers on the limbs and tail; etc).
>>> But over this same time, these tree-dwelling theropods didn't get
>>> around to evolving any arboreal characters. I find this perplexing.
>> That's only a problem if you assume that "trees-down" is an essential
>> part of the neoflightless hypothesis. It doesn't seem to me that it
>> is. The neoflightless hypothesis may still be valid if avialans
>> (apomorphy-based sense) developed flight from the ground up.
> Correct. The strict neoflightless hypothesis does not require arboreality.
> I think it did but that's another matter.
Curious to see your response to Tim's criticism, then.
I haven't seen any response to something Mike Habib posted earlier, too:
Michael Habib wrote:
> One of the reasons the dichotomy was thought to exist (and still does today)
> was a mistaken assumption that arboreal and terrestrial launch in birds are
> fundamentally different, which they are not. In fact, they are almost
If launching from trees and from the ground are "almost identical",
why would we need to invoke arboreality in animals that don't have any
signs of being arboreal?
T. Michael Keesey