A mock sauropod's nest is on display at "The World's Largest Dinosaurs" exhibition, an exhibition exploring the biology of sauropods, a group of the largest dinosaurs that ever walked the Earth, during a media preview at the American Museum of Natural History in New York, April 13, 2011. "The World's Largest Dinosaurs" exhibition, which will run from April 16, 2011 to January 2, 2012, draws on cutting-edge paleo-biological research to create an interactive exhibition around sauropods, a group of the largest-ever dinosaurs, some of which grew to be longer than 150 feet and weigh up to 90 tons, around 200 millions year ago. AFP PHOTO/Emmanuel Dunand (Photo credit should read EMMANUEL DUNAND/AFP/Getty Images)