Researchers find preserved dinosaur sitting on nest of eggs with fossilized embryos, first

The oviraptorosaur fossil was discovered in rocks 70 million years old in the city of Ganzhou, China, the Carnegie Museum of Natural History (CMNH) said in a press release in January.

Oviraptorosaurs were part of a diverse group of feathered, bird-like dinosaurs that lived during the Cretaceous Period.

“Dinosaurs preserved on their nests are rare, as are fossil embryos. This is the first time that a non-avian dinosaur has been found sitting on a nest of eggs that preserve embryos, in a single spectacular specimen,” he said. Shundong Bi, an CMNH researcher and professor at Indiana University of Pennsylvania, said in the statement. Bi and Xing Xu, a professor at the Chinese Academy of Sciences, were the main authors of an article announcing the discovery in Science Bulletin.

Some of the embryos in the eggs were visible as well as “the forearms, pelvis, hind limbs and part of the tail of the adult,” the CMNH said.

“The late stage of embryo development and the proximity of the adult to the eggs strongly suggest that the latter died incubating its nest, like its modern bird cousins, rather than laying its eggs or simply keeping its nest. -style crocodile, as has sometimes been proposed for the few other oviraptorid skeletons that have been found atop nests, ”said the CMNH.

The discovery revealed many details about the species, including the fact that dinosaurs fed their offspring.

“Although a few adult oviraptorids have already been found on nests of their eggs, no embryos have ever been found inside these eggs,” said Dr. Matt Lamanna, senior dinosaur paleontologist at the CMNH and another study researcher, in the release.

“In the new specimen, the babies were almost ready to hatch, which definitely tells us that this oviraptorid had maintained its nest for quite a long time,” Lamanna said. “This dinosaur was a caring parent who ultimately gave his life while feeding his young.”

The fossil also gave researchers insight into the diet of oviraptorosaurs, as the fossil was found with pebbles – most likely gastroliths, or “stomach stones” – in the abdominal region.

The dinosaurs would swallow the stones on purpose to help them digest their food. This is the first time that gastroliths have been found in oviraptorids, according to the CMNH.

“It’s extraordinary to think of the amount of biological information captured in this single fossil,” said Xu. “We will learn from this specimen for many years to come.”