It has always been assumed that dinosaurs laid eggs, as other large reptiles do. (dinosaur equipment)However, it was in the 1920s that the first dinosaur eggs were actually found. A series of expeditions into the Gobi Desert, led by Roy Chapman Andrews of the American Museum of Natural History, USA, uncovered several nests containing eggs and a large number of skeletons of the ceratopsian Protoceratops. For 70 years these uProtoceratops eggs” were the most famous and important dinosaur eggs found.(dinosaur manufacturer) At the site, the structure of the nest, the arrangement of eggs within it, and the proximity of the nests to one another were all clearly visible. It was suggested that there was evidence that the nests had been attacked. A small theropod named Oviraptor^ or egg-stcaler, was found close to one of the nests, having been overwhelmed by a sandstorm while trying to rob it. Then, in the 1980s, more of the same nests were found, again by an expedition from the American Museum of Natural History, but this time one of the nests had the skeleton of an Oviraptor actually sitting on it. The nests and eggs are now believed to be those of the Oviraptor.
At another site known as Egg Mountain in Montana, USA, nests with eggs and remains of the ornithopod Orodromeus were found, with remains of the theropod Troodon. The was first believed to be at the site intending to rob the nests, but the nests are now believed to be those of the Troodon. The Orodromeus remains arc thought to be from corpses that the parent theropods had brought back to feed their young. The provenance of the Troodon eggs was confirmed when some of the eggs were dissected and baby Troodon were found inside. However it is unusual to be able to dissect a dinosaur egg. (Dinosaur Playground Equipment)A fossilized egg is nn egg that died before it had a chance to hatch. When the egg dies the embryo inside is usually destroyed. Beetles burrow through the shell and lay eggs, and when the larvae hatch they eat the dinosaur egg’s contents. Most fossilized eggs contain only scraps of bone that are so jumbled that they are unidentifiable.
Shell fragments are often found associated with nesting sites, where the eggs came to maturity and hatched. Modern microscopy techniques have been used on shell fragments so that dinosaur egg shells can be compared with those of modern animals. It was once assumed that dinosaur eggs had soft or flexible shells, like modern reptiles.
However, study of the crystalline structure of fossil egg shells shows that the majority of them were hard and rigid, like those of birds.