Sinornithosaurus millenii venomous dinosaur fossil in China

Scientists unearth in China fossil of first-known dinosaur with venomous teeth

Picture: Sinornithosaurus Milleni, courtesy Times

The fossil of a feathered, “venomous” dinosaur, which lived about 125 million years ago, has been unearthed in north-eastern China.

The well-preserved fossil indicates that this dinosaur, called Sinornithosaurus millenii, could deliver poison thought its fangs to kill its prey. Some aspects of the teeth and skull of the creature, which could have been the size a turkey, point to the fact that it was venomous.

Photo: Sinornithosaurus Millenii fossil

Sinornithosaurus millenii was first described by scientists about 10 years ago, but the details of its cranial anatomy are being reported only now, according to David Burnham, a paleontologist at the University of Kansas, in Lawrence, the United States.

Burnham said most of the teeth in each side of the upper jaw of the Sinornithosaurus millenii had grooves, which ran from the base of each tooth to the tip – a characteristic found in some of the present-day venomous reptiles.

A big, triangular depression on the animal’s upper jawbone (a feature that was not earlier reported in other dinosaurs or their relatives) probably held contained glands that produced venom, David Burnham and his colleagues reported in the online edition, dated December 21, 2009, of the Proceedings of the National Academy of Sciences, of the United States.

The research was conducted by scientists from the University of Kansas, in Lawrence, the United States, and Northeastern University, Boston, Massachusetts, the United States.

It was likely that the venom that flowed from those glands “pooled in reservoirs” at the base of each grooved tooth till the Sinornithosaurus millenii bit its prey.

The anatomy is found similar to that of ‘rear-fanged’ snakes like the boomslang that do not inject poison directly through front-fangs, “but funnel it along grooved teeth as they pierce the skin of their prey,” the researchers said in the report.

Some of the narrow teeth of the creature were a little longer than the others, and the present-day animals that have a similar variability in the length of tooth normally bite and hold their prey.

From this, David Burnham and his colleagues conjecture that the Sinornithosaurus millenii could have used its venom to stun its victims. The victims could probably have been birds.

According to Burnham, the new finding offers the strongest evidence, so far, for the evolution of venom in dinosaurs. The idea of venomous dinosaurs has intrigued scientists for long.

In fact, the dinosaur species Dilophosaurus was depicted in the movie Jurassic Park as spitting venom. However, till now, there were no fossil records to support this.

A grooved tooth, believed to belong to a theropod dinosaur, was unearthed in Mexico in 2000. The discovery, according to many scientists, indicated that the dinosaur might have “funneled” venom into its prey.

Now, more and extensive evidence of the ‘venomous dinosaur’ has been found in the fossil of the Sinornithosaurus.