The October 13, 2004,
National Geographic News carried a story on the new dinosaur recently
discovered in China, quickly dubbed, "The sleeping dragon." because of
its posture. The new fossil specimen is an almost fully grown adult.
It sits on long, folded hind limbs. Its forelimbs are folded birdlike
next to its body and its neck curves to the left, so that its
relatively small head lies between the left elbow and body. "I
never expected we'd find a sleeping dinosaur in general, let alone
with the tuck-in position," said Xu Xing, a curator
at the Institute of Vertebrate Paleontology and Paleoanthropology in
Mark Norell, chairman of the division of paleontology at the
American Museum of Natural History in New York, said the discovery
further strengthens the chain linking dinosaurs and birds, suggesting
this birdlike sleeping posture first evolved in dinosaurs.
"This is another stereotypical bird behavior in another nonavian
theropod," he said. Theropods are meat-eating dinosaurs characterized
by short forelimbs and powerful hind legs. Many scientists believe
small theropods are ancestors to the first birds. The posture is
identical to the "tuck-in" posture of many living birds, according to
Xu and Norell.
Mei long was found in layers of volcanic and riverbed
sediment that have been dated to about 130 million years ago. At that
time, Liaoning Province was a volcanically active, forested region
filled with lakes and streams. "It is kind of difficult to imagine how
a fossil can be preserved in such a posture. It must be like it
instantly died and was buried," Xu said. Scientists are uncertain as
to exactly how the fossil was preserved. Sues and Philip Currie,
curator of dinosaurs at the Royal Tyrell Museum in Alberta, Canada,
point out that an incomplete troodontid skeleton from Mongolia,
Sinornithoides, was discovered in 1994 in a similar pose.
"Overall, I think [Mei long] is a very remarkable find and is
especially amazing because it is the second small troodontid in this
pose," Currie said. "Not much doubt that this is the way they slept."
While feathered-dinosaur discoveries are becoming almost routine,
the discovery of a sleeping dinosaur is a rare surprise, Norell said.
"There are so very few fossils of animals which are basically buried
alive, preserving behavior that's interesting."