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Fwd: [wcti] Cute little 7-pound dinasours found in China




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Cute little 7-pound dinasours found in China
By LEE BOWMAN
Scripps Howard News Service
March 20, 2002

- An early ancestor of the mighty Triceratops found in
China weighed in at a diminutive 7 pounds and had the
beginnings of horns and a short frill that
characterized one of the more flamboyant-looking lines
of Cretaceous creatures.

Paleontologists working in northeast China have
unearthed two specimens of an animal they call
Liaoceratops yanzigouensis, which was about the size
of a hare.

"This small, primitive dinosaur is actually more
interesting to science in many ways than its larger,
more famous relatives because it teaches us more about
evolution,'' said Peter Makovicky, a co-author of a
report on the fossils published Wednesday in Nature.
Xing Xu of the Chinese Academy of Sciences led the
expedition.

"Basal (primitive) dinosaurs are crucial because they
help us tie different groups of dinosaurs together and
map out evolutionary patterns."

The fossils, dated to 125 million to 145 million years
ago, go back nearly to the roots of a family of
dinosaurs known as ceratopsians, which later branched
into two groups, one called neoceratops, with the
distinctive horns and frills, the other a
parrot-beaked clan.

"Liaoceratops establishes that this split occurred no
later than the earliest part of the Cretaceous period,
about 130 million years ago,'' Makovicky said. "And it
indicates that ceratopsians acquired some of their
distinctive features earlier and more rapidly than was
previously recognized.

"It also demonstrates that the large, spectacular
species that grace many museum exhibits are descended
from some very small ancestors.''

Liaoceratops (pronounced lee-ow-cer-a-tops) was indeed
diminutive, with the adult skull measuring just 4.4
inches, and the entire animal measuring less than 3
feet from snout to tail, and standing perhaps a foot
high.

It had a small horn facing sideways under each of its
eyes that seem to be for display rather than any
practical use, and the beginnings of a frill, as well
as a blunt nose.

"Pitted surface texture of the rim of the frill
clearly indicates that the jaw muscles passed behind
the cheek and were attached to the frill,'' Makovicky
said. "Although short, the frill is thick to
counteract the contraction of these large muscles.''

It had teeth that were built mainly for slicing and
shearing tough plants - leaves of ginkgo, horsetails
and conifers are preserved in the same rock structures
of the Yixian Formation where the dinosaur fossils
were found.

Despite filmmakers depicting pitched battles between
giant leaf-chomping armored dinos and meat eaters
later in the Cretaceous, the scientists say there's
little evidence that ceratopsians' horns or frills
evolved for use as weapons. It's just as likely they
were used for courtship or intimidating rivals as for
skewering a Tyrannosaurus Rex.

"Liaoceratops appears unable to protect itself against
most predators, which would have included carnivorous
dinosaurs and crocodiles,'' Makovicky said. "Instead,
it probably relied on concealment or flight to defend
itself.''


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Ronald I. Orenstein Phone: (905) 820-7886
International Wildlife Coalition Fax/Modem: (905) 569-0116
1825 Shady Creek Court
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