March 25, 2008

New Dinosaur Species Discovered in Mexican Desert

New Species believed to be related to the Triceratops

Paleontologists have discovered the fossil of a new dinosaur species in Mexico's Coahuila desert. The scientists said the plant-eating dinosaur lived 72 million years ago, and had three giant horns it used to fight predators and attract mates.  

Now filled with rocks and cactus, the Coahuila desert was once covered by ocean waters, and dinosaurs of all types used the jungle-filled beaches to hide from an enormous, fierce predator that was a relative of the legendary Tyrannosaurus rex.  

The scientists discovered evidence that the new species is related to the Triceratops, known to have the largest head of any animal that ever existed.

However, at around 23 feet, the new species is slightly smaller than most Triceratops, but its three-foot-long horns were just as large. And holes in the dinosaurs neck frill would also have set it apart.

Scott Sampson, a curator from Utah Museum of Natural History, who along with Mexican investigators helped make the discovery, said the scientific name of the new dinosaur will not be revealed until the end of the year. It will be only the second dinosaur species named in Mexico, and follows an announcement in February of a new duck-billed dinosaur from the same region called Velafrons coahuilensis, which roamed the ancient beaches in large numbers.

The paleontologists expect to find evidence of dozens of other new dinosaur and plant species buried in the Coahuia desert in the near future.  

"This is just the beginning," Martha Aguillon, a paleontologist at the local museum near the Rincon Colorado fossil beds in Mexico's northern state of Coahuila, told Reuters.

Paleontologists speculate the dinosaur likely used its gigantic horns to fight off meat-eating predators and demonstrate dominance in head-butting battles with other males.  It's its flashy head armor and neck frills, however, were used in courtship rituals to attract mates.

"That whole section of the head was for sexual display, it was all ornamentation," paleontologist Terry Gates told Reuters. Gates works with Sampson at the University of Utah museum, and is also one of the scientists behind the discovery of the 35-foot Velafrons.

Vegetarian dinosaurs such as the new three-horned species and the much-larger Velafrons used their size to protect them from brutal predators like the local cousin of the giant T-rex.

"The Tyrannosaur in Coahuila was a little smaller (than the T-rex) but still nothing you would want to run into in a dark alley," Sampson explained. "It was more than 30 feet long and rather intimidating."

The dinosaur discoveries are shedding light into life in the late Cretaceous Period on the southern parts of western  North America. During that time, the continent was divided in two by a large inland sea stretching from the Arctic Ocean to the Gulf of Mexico. The tropical environment provided a perfect habitat for a wide variety of wildlife.

"The land mass these animals lived on was less than one-fifth the size of present-day North America yet we have all of these different elephant-sized animals," said Samson.

Gates explained that Mexico was unique in that sea levels rose and receded over thousands of years, forcing animals to either adapt to new environments or face extinction. Clues from tens of millions of years ago can help scientists understand how nature might react to rising sea levels today, he said.

"We have very little knowledge of the response of land animals to sea level rise," he said. "That's exactly why I want to do this study."


Photo Caption: Triceratops statue, Royal Belgian Institute of Natural Sciences (Natural History Museum)


On the Net:

Utah Museum of Natural History

RedOrbit Article - "Dinosaur Find Reveals Wet History of U.S."