China's Gobi desert source of rare dinosaur finds

Italy's famous city of Pompeii was buried its way of life frozen in time in the volcanic eruption of Mount Vesuvius in A.D. 79.

Sereno, a paleontologist, helped lead the 2001 expedition that uncovered the fossilized remains of the 25 young sinornithomimus near Suhongtu, a tiny, remote village in the Gobi desert about 370 miles (600 kilometers) west of Hohhot.

The position of the dinosaur bones suggests they were looking for water on the edge of a lake, got stuck and died as the mud engulfed them, Sereno said in a telephone interview. Their hip bones were found at odd angles, indicating scavengers tugged at their carcasses. Crablike organisms were also found surrounding the skeletons, a clue that tells scientists they were covered in water shortly after death, which helped preserve them.

Tan Xinwei, a paleontologist from the Inner Mongolia Department of Land and Resources who also worked on the expedition, said the findings tell researchers that "the youngsters were left to fend for themselves while the adults were preoccupied" with hatching eggs or building nests.

The two-legged, feathered dinosaurs reached about 4 feet (1.2 meters) tall as adults and scavenged for small plants by jutting out their long necks in an ostrich-like fashion, Sereno said.

Xue Xing, a professor at the Institute of Vertebrate Paleontology and Pale anthropology in Beijing, called the findings "an important discovery" that could only have happened under a unique set of circumstances.

"Without the correct environmental conditions, these fossils would not have been found in nearly pristine condition uncrushed or worn down," said Xue, who was not involved with the project.

The bones were spotted in 1978 by a Chinese geologist and first excavated by a Sino-Japanese team some 20 years later. That team named the dinosaur’s sinornithomimus, or  "Chinese bird mimic."

It wasn't until 2001 that researchers were able to unearth all 25 skeletons and examine their findings.

The sinornithomimus skeletons were brought to the University of Chicago for research and preservation but will return to China by the end of the year.

The 10-member expedition and research team included scientists from the University of Chicago, the Chinese Academy of Sciences, Montana State University, the University of Michigan and Inner Mongolia's Department of Land and Resources. It was financed by the National Geographic Society.