In Argentina this year, scientists digging on a site made a fantastic discovery, which made them realise that dinosaurs lived as a large family. The site consisted of many nests with each nest containing as many as 15 to 30 eggs. The eggs belonged to a plant-eating dinosaur called Titanosaurs. It is the biggest nesting site of dinosaurs found so far.
The word dinosaur is a Greek word meaning giant reptile. Most reptiles lay eggs in nests but they walk away after the young hatch to fend for themselves.
However, the discovery of this site and an earlier site discovered in 1978 in Montana, USA, has made scientists change their views about the dinosaurs.
In Montana, eggs and skeletons of adults, babies and young teen dinosaurs were all found in one site. In other areas fossil footprints were found in large numbers suggesting that these dinosaurs lived as a family and travelled as a herd.
At other sites the dinosaurs had communal nesting sites, or nests at the same place. These nesting sites or rookery are similar to current day turtle nesting sites in Orissa, India, where a large number of turtles come together to lay eggs.
Scientists have also discovered that flesh-eating dinosaurs sometimes hunted in packs. Two or three of them would attack a single prey and kill it. This is unusual as it was thought that only mammals like the wolves hunt in packs. Fossils show the skeleton of a Tenontosaurus found near the skeletons of three carnivorous (flesh-eating) Deinonychus.