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Jehol Biota exhibit in Vancouver



From: Ben Creisler bh480@scn.org
Took a quick one-day trip up to Vancouver, British 
Columbia, last Saturday to see the "Jehol Biota" exhibit 
of specimens from the private collection of  Du Wenya, who 
runs a  museum in Jinzhou, China. (The exhibit at the 
Vancouver Convention and Exhibition Centre ends 12-23-02.) 
Apparently the Chinese government will not allow such 
exhibitions of private specimens in the future so this 
show is a rare event. According to a story in the 
Vancouver Sun, some of the specimens are new to Western 
scientists. Most notable for purposes of the Dinosaur 
Mailing List were three specimens identified only 
as "dromaeosaurs"--based on some obvious differences in 
limb proportions, they would appear to represent at least 
three distinct taxa but maybe not "new" taxa in every 
case. Also on display were around a dozen specimens of 
Confuciusornis (including the holotype of Confuciusornis 
dui and another specimen that is clearly NOT 
Confuciusornis despite the label) and around a half-dozen 
specimens identified as Liaoxiornis. Other items include 
specimens of Psittacosaurus (one beauty (D:058) has 
gastroliths in situ in the gut region), many fossils of 
the diapsid Hyphalosaurus (mislabled "Hyphiosaurus" 
throughout), plus amphibians, fish, insects and plants. 
Sorry to say I can't give a detailed Tom-Holtzian analysis 
of the dromaeosaurs, but here is some basic info. Catalog 
numbers are for the Wenya Museum:

Dromaeosaurs:
All three of these theropods have caudals bearing very 
long thin processes to stiffen the tail and two specimens 
at least have an enlarged claw on the 2nd toe. The dates 
on the labels are "Late Jurassic" but the fossil almost 
certainly date to the Early Cretaceous instead. Nicknames 
are mine.
DNO: 087 "Long femur"
A virtually complete and apparently undoctored specimen 
around 64 cm long with a complete but crushed and somewhat 
jumbled skull. The femur is about 1.25 times the size of 
the tibia. Outline of filaments are visible in the pelvic 
region and possibly elsewhere. My hunch is that this one 
may be a Sinornithosaurus, but I'll need to check the 
original description.

DNO: 088 "Long Tibia"
An incomplete specimen apparently from a single 
individual, preserving the skull, forelimbs, hindlimbs and 
tail, but most of the trunk section is missing. It was 
displayed in a large case so close examination was not 
possible. The tibia is about 1.25 times longer than femur. 
Femur and metatarsals about equal in length. Humerus and 
ulna about equal in length. Manus disarticulated. The 
crushed skull was hard to decipher from a distance.  Based 
on the limb proportions this is not the same as DNO: 087, 
and I won't guess if it's a known or new taxon. It also 
appears somewhat smaller than the possible 
Sinornithosaurus specimen above.

D: 090 "Short Metatarsals"
I have strong suspicions about this one, even though its 
photo is part of the hand-out brochure.  The feet are 
definitely doctored and lack a large slashing claw despite 
the "dromaeosaur" label. John Hutchinson has a quick 
description of some Wenya specimens on the web (see  
http://www.geocities.com/CapeCanaveral/Hangar/6878/sape.htm
l). He mentions a chimaeric dromaeosaur with 
Confuciusornis feet. This may be the same specimen, though 
I didn't see any obvious preserved filaments anywhere on 
the specimen. The metatarsals appear abnormally short and 
the feet are almost preposterously dainty for the rest of 
the animal. The matrix is clearly repaired and glued in 
the vicinity of the feet. The rest of the body is also 
odd, with one arm at least having extremely long radius 
and ulna and no preserved hand bones--the other arm has 
part of the radius and ulna missing and the manus mangled. 
The skull appears to have teeth only in the front of the 
jaws instead of along the length of the jaws. An expert 
may have to sort out the avian from the non-avian parts 
before much can be said about this one.

-----
Birds:
Many excellent fossils of Confuciusornis representing 
different growth stages and presumably sexes (one slab has 
two individuals, one with two very long display feathers 
on the tail, the other without), and at least two species 
(C. sanctus and C. dui). Many have very well preserved 
wing feathers. It's staggering to think that there may be 
thousands of virtually complete fossil specimens of this 
ancient bird.
One specimen (BNO: 081) labled "Confuciusornis sanctus" 
has teeth, and a manus with a third digit shorter than the 
second--all three digits were not nearly as robust and 
heavily clawed as the typical Confuciusornis manus while 
the feet had very large claws, again unlike 
Confuciusornis. I'll need to check Hou's book, but this 
one is probably a known enantiornithine.

The multiple Liaoxiornis specimens are of particular 
interest since previously this taxon was known from a slab 
and counterslab given different names.  Of particular note 
was a specimen (B: 077) labeled Liaoxiornis with a 
question mark, that preserves two large tail feathers 
extending beyond the relatively long bony tail. Maybe such 
double tail feathers (known from much longer examples in 
Confuciusornis and maybe Jibeinia) were typical sex-
markers in mature male Mesozoic birds. Another very tiny 
specimen (obviously juvenile) was preserved on a slab and 
counterslab ( B:066 and B:067).

-----
The insect fossils are quite impressive, not only for the 
size of some bugs but for the excellent preservation. It's 
a bit strange that insect fossils are actually rarer than 
vertebrate fossils, since insects obviously have 
outnumbered vertebrates since the Carboniferous.  A nice 
specimen labeled Kalligrama (MN: I129) preserves the 
classic big eyespot pattern found on some modern insect 
wings. Apparently the image of big eyes worked to make 
pterosaurs, primitive birds and small dinosaurs think 
twice. 

Other specimens of particular note included some parts of 
Archaefructus, one of the earliest known flowering plants, 
the frog Callobatrachus (with muscles preserved) and the 
salamander Liaoxitriton.

I avoided the guided tour--the Anglo guide was obviously 
enthusiatic about the exhibit but made up much of his 
spiel out of thin air. Overheard quotes included a 
description of Psittacosaurus as a "tree-hopper" (not 
impossible I guess but certainly not a "fact") and 
something about a new specimen of  T. rex from Montana 
from the "Late Jurassic" that had "a diaphronous 
extension" that showed it was trying to evolve.  People 
appeared to eat it up. The labels were annoyingly garbled, 
with names of taxa mispelled and some loopy English 
translations that must have been run through a computer 
translation program.

Still, the best fossils on display are so amazing in their 
completeness and preservation of detail that it's hard to 
be a quibbler over defects and shortcomings in the 
presentation.