from the book, "Our Fascinating Earth"
In the late 1970's a number of dinosaur nests were discovered in the eroded badlands of Montana. Under the direction of paleontologist John Horner more than 500 partial and complete eggs of a dinosaur, later named Maiasaura (good mother lizard), have since been excavated. Many were found in nests, making this a most important contribution to scientific knowledge of dinosaurian family life. Spectacular as this discovery may have been, it is not the first time dinosaur nests still containing embryonic and baby dinosaurs have ever been found.
About one hundred million years ago a female ceratopsian (horned—face) dinosaur scooped out a shallow hole in the desert sands of what is now Mongolia. When the hole was dug, she laid a dozen or so eggs inside it and covered the nest with sand. Satisfied that her task was completed, she turned back to the never—ending business of finding food. Doubtless she seldom wandered far from her nest and periodically returned to fight off egg predators. Her efforts were all in vain, for the eggs never hatched. A violent desert sandstorm covered the nest with a thick layer of windswept material, closing off the air supply. Eventually the eggs became petrified.
In 1922, under the leadership of naturalist Roy Chapman Andrews, an American Museum of Natural History expedition uncovered the nest in the Flaming Cliffs area of the Gobi Desert. Apparently the incident just described had occurred numerous times for hundreds of egg fragments were found along with many dozens of nests. Some of the eggs were dissected by the scientists and were found to contain the unhatched skeletons of infant dinosaurs.
More than one hundred adult skulls were also found in the area. With such a concentration of a single species, ranging from egg to adult, it is quite evident that the Flaming Cliffs area of Mongolia was at that time the breeding ground for this group of dinosaurs. They probably gathered there each year by the thousands to mate and bear their young. This species has now become one of the most thoroughly studied of all dinosaurs.
Protoceratops (first horned face) existed in herds on this prehistoric Mongolian desert. It grew up to six and a half feet long and had an enormous head with a hooked parrotlike beak and a large bony frill that covered its neck. After laying her eggs, the female probably returned to the herd to feed but always remained in the vicinity of the nest. Parental instincts would prescribe that she periodically return to the nest, and it may be that, like the modern crocodile, she helped her young into the world. It is also very likely that her brood had its share of enemies, as do the young of modern crocodiles.
In one instance the American expedition team of 1923 was in the process of excavating a particular nest when, to their amazement, they uncovered the skeleton of a four—foot toothless dinosaur about three inches above the eggs. Later named Oviraptor (egg seizer), the animal probably made its living by feeding on dinosaur eggs. This particular specimen was in the act of digging up the nest when it was overcome by a violent sandstorm and buried alive on top of the very eggs it had come to steal.
There were other enemies; one known to scientists was a fast—running carnivore of Jurassic Park fame, the movie star Velociraptor (swift robber). One hundred million years ago this fierce carnivore had other things in mind than making monster movies. Velociraptor was about the size of Protoceratops but lighter and, armed with huge teeth and enormous, vicious claws, much more agile. It probably made easy meals from very young hatchlings rather than from stolen eggs as did the Oviraptor. The carnivore may have been drawn to a nest by either the sight or sound of cracking shells. The mother Protoceratops, attracted by the resulting commotion, would spring to the rescue of her hatchlings, and a battle royal would ensue. The carnivore was usually the winner, but not always.
Eons ago a mother Protoceratops returned to her nest to find a Velociraptor in the very act of consuming her young. A death struggle began, and the nest robber managed to kill the Protoceratops. Of course Protoceratops, with a parrotlike beaked skull powered by enormous jaw muscles, was not exactly a pushover. As the Velociraptor grasped her bony frill and slashed with its terrible claws, its own life ebbed away.
In 1971 a joint Polish—Mongolian expedition uncovered their remains. The forelimbs of Velociraptor were still holding on to the large frill of Protoceratops, just as they had in that battle to the death more than one hundred million years ago!