Paleontologists have discovered fossilized turtles from the Jurassic era in China's northwest province of Xinjiang.
A team of researchers from the University of Tübingen in Germany and Berlin Natural History Museum has been working with Chinese paleontologists since 2008 and, while working with them, found about 1,800 fossils of mesa chelonia turtles (see photo) in the region.
The result of the study, "An enormous Jurassic turtle bone bed from the Turpan Basin of Xinjiang, China," has been published recently in the German journal Naturwissenschaften.
"This site has probably more than doubled the known number of individual turtles from the Jurassic," said Walter Joyce, fossil turtle specialist from University of Tübingen, said in a statement.
"Some of the shells were stacked up on top of one another in the rock," he said, referring to the finding as a bone bed that has only turtle remains.
Xinjiang is one of the world's driest regions today, but about 160 million years ago, it was a green place with lakes and rivers. However, the region also faced seasonal drought causing a major impact on the survival of the turtles.
Researchers studied the site and the layers of its stones to determine what caused the turtles to die. They suggested that the turtles might have gathered in one of the remaining waterholes during the dry period, waiting for rain.
But the rain arrived very late, and many turtles had already died leaving their bodies to rot. The river washed the turtles along with the sediments, dumping all the turtles in one place. Experts noticed this bone bed with more than 1,000 fossilized turtles.
The new discovery will allow researchers to conduct statistical analysis of the ancient species. This will also help them to compare the growth, variability and morphological differences between different species.