Lamar University professors Jim Westgate and Jeff Pittman travel to Canada this week to present the recent discovery of a 40-foot long crocodile in Mexico.
The pair will present the work of their international research team and its discovery of the first evidence of the species Deinosuchus riograndensis in Mexico. The two will address researchers at the 66th annual meeting of the Society of Vertebrate Paleontology in Ottawa, Canada.
Teeth and bony armor of Deinosuchus were found in desert exposures of sedimentary layers deposited on the coast of Chihuahua some 70 million to 80 million years ago as the shoreline slowly moved from near Ojinaga, Mexico to the southernmost part of Big Bend National Park as the Rocky Mountains began to uplift.
“At that time, the giant crocodile was the dominant predator in the swampy coastal habitats and preyed on duckbills and other dinosaurs for food,” said Jim Westgate, a professor of geology who holds a Ph.D. from the University of Texas. “Although remains of Deinosuchus have been found from dinosaur age deposits in the Big Bend region of Texas, the southeastern U.S. and in Montana, our discoveries in Chihuahua are firsts for Mexico.”
Deinosuchus riograndensis is a contender for the title of Earth's supreme predator. Its name means 'terror crocodile' and it is well deserved because Deinosuchus is a dinosaur eater. Dinosaur bones have been found in the Big Bend region that are heavily damaged and covered with distinctive crocodile bite marks. The fossilized remains of these gigantic crocodiles, among the largest crocodiles ever known, have been discovered in the south-central part of the Big Bend National Park.
With lengths of 40 feet and jaws studded with 6-inch teeth, these powerful predators were extraordinarily equipped to feed upon a variety of dinosaurs. Just like modern day crocodilians, Deinosuchus riograndensis probably hunted by ambush, lying submerged near shore, and violently seizing large dinosaurs as they foraged amid the vegetation of Big Bend's ancient swamps.
Westgate and Pittman, a lecturer in geology at Lamar, were joined in Chihuahua by Ben Brown of the Instituto Nacional de Antropologia E Historia, Chihuahua, Dana Cope of the College of Charleston, and Jon Kalb of the Vertebrate Paleontology Laboratory, Texas Natural Science Center in Austin.
Fossils associated with the croc remains provide evidence that Deinosuchus was a top predator in a diverse coastal community which included duckbilled and horned herbivorous dinosaurs, as well as raptors and a Tyrannosaurus Rex relative named Albertasaurus, Westgate said. Skeletal remains of turtles and smaller crocodile species are common, while leaf and petrified wood indicate a forest of Norfolk Island pines and palm trees grew along the coast. Local estuarine deposits have yielded remains of several species of sharks, rays and gar amongst brackish water oyster reefs.
Funding for the team’s field expeditions has been provided by LU Research Enhancement grants and funds from Mexico's Instituto Nacional de Antropologia E Historia and the College of Charleston.
The prospect of making another “first” discovery for the region will have the team watching their steps closely this winter. Westgate and the team plan a January 2007 expedition to prospect outcrops freshly scoured by desert rains from 2006 Pacific hurricanes. “More fossils are likely to have been exposed due to the heavy rains of last year,” Westgate said.
