[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: Greg Paul is right (again); or "Archie's not a birdy"
- To: Dinosaur Mailing List <dinosaur@usc.edu>
- Subject: Re: Greg Paul is right (again); or "Archie's not a birdy"
- From: Jason Brougham <jaseb@amnh.org>
- Date: Thu, 28 Jul 2011 12:31:04 -0400
- Authentication-results: msg-ironport0.usc.edu; dkim=neutral (message not signed) header.i=none
- References: <D349457A-B366-4323-8230-CE7204335B81@amnh.org>
- Reply-to: jaseb@amnh.org
- Sender: owner-DINOSAUR@usc.edu
Certainly Epidexipteryx could be secondarily terrestrial. Then again,
Epidexipteryx RETAINS the ribbon like tail feathers, which Xu postulated as
primitive relative to flight feathers. Therefore, Epidexipteryx may be the
primitive one and retained primitive flightlessness, and flight may have arisen
in an animal closer to what Xu calls (in all three relevant studies mentioned
here) Epidendrosaurus and then been passed on to birds.
Then, in Xu's new cladogram, there is less support for the hypothesis that
Archaeopteryx or any deinonychosaur could fly or glide, as none of them are
ancestral to nor closely related to birds. There is no more support for the
hypothesis that any of them were flightless, either.
But, as Dr. Holtz and Mr. Paul have said, this new topology is not strongly
supported and may change again.
> On Jul 28, 2011, at 11:55 AM, Matthew Martyniuk wrote:
>
>> _Scansoriopteryx_, though, seems to have had relatively long wings
>> feathers (considering it is known only from fledgling specimens) that
>> form a herringbone pattern characteristic of remiges. The small arms
>> and lack of remiges in _Epidexipteryx_ look like a secondary loss.
>>
>> Matt Martyniuk
>>
>> On Thu, Jul 28, 2011 at 11:29 AM, <GSP1954@aol.com> wrote:
>>> There was no way that small armed Epidexipteryx flew. But its actual
>>> phylogenetic placement is tenuous and it may have descended from Jurassic
>>> fliers.
>>> I doubt we will ever be able to sort a lot of this out. In any case my basic
>>> notion was that Archaeopteryx was less derived than some "dinosaurs," and
>>> that some of the latter were secondarily flightless, which seems to be
>>> holding up pretty well.
>>>
>>> GSPaul
>>>
>>>
>>> In a message dated 7/28/11 9:34:25 AM, jaseb@amnh.org writes:
>>>
>>> << The new paper on Xiaotingia places scansoriopterygids as the most basal
>>> avialans, and Xu has opined that Epidexipteryx was flightless, raising the
>>> possibility (though by no means requiring) that the last common ancestor of
>>> Archaeopteryx and crown group birds was flightless.
>>>
>>> That doesn't fit your theory, correct? >>
>>>
>>> </HTML>
>>>
>
> Jason Brougham
> Senior Principal Preparator
> American Museum of Natural History
> jaseb@amnh.org
> (212) 496 3544
>
>
Jason Brougham
Senior Principal Preparator
American Museum of Natural History
jaseb@amnh.org
(212) 496 3544