Dinosaurs, party of six, meat eating

Traditionally, big meat eaters like Tyrannosaurus rex and Giganotosauris have been viewed as solitary eat-and-run types. Now, the discovery of a dino dinner party may reform the image of the carnivorous lifestyle.

Scientists found bones from six members of a new species of giant meat-eating dinosaur squished into the mud of a fossil bed in Patagonia. Over 40 feet long with knifelike, 4-inch-long teeth, these new carnivores may have been even bigger than Giganotosaurus, says paleontologist Philip J. Currie of the Royal Tyrrell Museum of Palaeontology in Drumheller, Alberta.

Despite their fearsome size, the dinosaurs would have been dwarfed by the gargantuan plant eaters that roamed the Southern Hemisphere at the time. “One tiny, little 5-ton animal is going to have trouble taking down a 100-ton animal. It might need a little help,” says Currie.

Scientists knew that some small carnivores hunted in packs, but this group of animals presents the first evidence of social behavior in big, meat-eating dinosaurs, says Don Lessem of Newton Highlands, Mass., founder of the Jurassic Foundation, an organization that promotes dinosaur research.

Currie announced the find on March 10 at the opening of a dinosaur exhibit at the Riverfront Arts Center in Wilmington, Del.