Thursday, July 5, 2007

Paleontologists discover pterosaur fossils in the Sahara



Giant flying reptile lands on Chicago's West Side
Paleontologists discover pterosaur fossils in the Sahara
© University of Chicago

A new species of pterosaur with a 16-foot wingspan has been discovered in the southern Sahara by a team led by University of Chicago paleontologist Paul Sereno. "This find puts African pterosaurs on the map," said Sereno, who is also an explorer-in-residence at the National Geographic Society.

Previous finds of these winged reptiles in Africa had been limited to individual bones or teeth. The 110-million-year-old fossils include most of one wing and several slender teeth from its over-sized jaws. "To find a wing composed of a string of paper-thin bones in a river deposit next to the sturdy bones of dinosaurs is a remarkable feat of preservation," Sereno said. The bones and teeth were found in Cretaceous-age rocks in Niger that were deposited by ancient rivers. Near the pterosaur site, Sereno's team also found bones of the 35-foot-long, sail-backed fish-eater Suchomimus and the enormous crocodile Sarcosuchus, dubbed "SuperCroc." "Definitely a fish-eater," remarked Sereno, who will describe and name the new species with David Blackburn, an expedition member from the University of Chicago and now a graduate student at Harvard University.

Like its contemporaries Suchomimus and Sarcosuchus, it dined on the abundant fish in the rivers, as evidenced by its long and slender teeth. As the jaws closed, the teeth interlocked to snare fish, leaving signs of wear on their sides."Somehow this huge species was able to fish on the wing. We imagine a pterosaur soaring over the water and somehow stalling to snag a fish," Sereno said. "It was a tremendous animal."

Based on numerous trackways, paleontologists now believe that pterosaurs were relatively clumsy on land or in shallow water, walking slowly on all fours. The African species preserves sharp hand claws on the front edge of the wing, which probably helped it climb when on land. The African pterosaur resembles another species discovered previously in the highlands of Brazil. When the Niger species lived, 110 million years ago, South America and Africa were just beginning to eparate."Pterosaurs wouldn't have had much trouble getting across at that point, so it's not surprising to find a close relative over there," Sereno said.

A life-size skeleton and flesh reconstruction of the new pterosaur, the first for a species from Africa, will go on display in Chicago's Garfield Park Conservatory, 300 N. Central Park Ave., as part of the "GIANTS" exhibit. The exhibit, created by Sereno's educational organization Project Exploration, opens Dec. 20 and will run through Sept. 6, 2004.

The flesh model incorporates the latest information on pterosaurs. "Pterosaurs are close cousins of the dinosaurs but had a very different look and lifestyle. Their bodies were covered by hair-like structures that arose independently from the hair we know today on mammals," Sereno said. The flesh model also has translucent wings, as scientists now believe from detailed impressions that the skin forming the wing would have allowed light to pass through. For more information on GIANTS, see www.dinogiants.org.

2 comments:

Anonymous said...

I've heard if the scientists want to preserve Dinosaurs' bones perfectly they have to create a solution made of generic viagra with other chemicals.

Inhumanoid said...

raymeds did a great compilation of articles about pterosaur. but the impressive part, it is that it is in the middle of the reptiles and birds.