Re: Epidexipteryx

[dinoboygraphics@aol.com]

Thanks to Jeff for the write-up.

> > > THey also say its claws show it could climb [snip] about as well as
Microraptor.<<<

I certainly can't disagree with that...


Scott Hartman
Science Director
Wyoming Dinosaur Center
110 Carter Ranch Rd.
Thermopolis, WY 82443
(800) 455-3466 ext. 230
Cell: (307) 921-8333

www.skeletaldrawing.com


-----Original Message-----
From: Jeff Hecht <jeff.hecht@sff.net>
To: Dinosaur mailing list <dinosaur@usc.edu>
Sent: Thu, 23 Oct 2008 7:25 am
Subject: Epidexipteryx



My New Scientist story is on-line this morning at 
http://www.newscientist.com/article/dn15017-halffeathered-dinosaur-was-a-bit-of-a-showoff.html?DCMP=ILC-hmts&nsref=news1_head_dn15017

Epidexipteryx  is a fascinating critter. I've corresponded with the 
authors, and
wasn't able to get all the details into my story, so I'll add a few 
bits here.

This comes from the same fossil beds as Pedopenna ("feather foot") and
Epidendrosaurus, which are now radiometrically dated at 152-168 million 
years.
The geology is pretty complex, and I think the dates are still 
controversial,
but this definitely is an older fauna than the Jehol, and if the dating 
is right
probably is older than Archaeopteryx (with the caveat that 
Archaeopteryx itself
is not firmly dated on a radiometric scale).

So what we're seeing are little feathered dinosaurs, but nothing yet 
with flight
feathers or true wings, in the sense they could be used for flight or 
even
gliding. Obviously finding more fossils is very very important, and I'm 
sure
IVPP is working on that. Judging from what has come out so far, the 
Daohugou
either is not as fossil-rich as the Jehol deposits or they haven't 
found the
mother lode of fossils.

Zhang et al say the tail is complete and its vertebrae differ from 
those of
Epidendrosaurus, supporting the idea the two are different. It would 
obviously
be very nice to have more fossils to get growth sequences of the two. 
There are
very faint feather impressions on Epidendrosaurus, and downy feather 
impressions
from the whole body of Epidexipteryx, not just on the shoulders where 
they are
clearest in the photos.  Thus the downy covering on the reconstructions.

THey also say its claws show it could climb, probably about as well as
Microraptor.

All of which leaves us with a diverse range of little feathered 
dinosaurs
closely related to birds running around the late Jurassic and early 
Cretaceous.
The tail display feathers show internal structures somewhat similar to 
- but
significantly different from - flight feathers. So it looks like 
evolution was
experimenting with different forms of the things that eventually became 
what we
recognize as feathers. Maybe Alan Brush can weigh in with his 
observations when
he has a chance to study the paper more carefully.

Anyway, it's a wonderful fossil, and I am looking forward to seeing 
more.
--
Jeff Hecht,    science and technology writer
Boston Correspondent, New Scientist magazine
525 Auburn St.,   Auburndale, MA 02466   USA
V 617-965-3834    e-mail jeff@jeffhecht.com
Web  http://www.jeffhecht.com