Scientists have made a major discovery in Ganzhou City in southern Jiangxi province in China. They found the remains of a dinosaur sitting on its nest of petrified eggs.
The dinosaur, an oviraptorosaur (oviraptor), belongs to a group of bird-like teropod dinosaurs that peaked during the distant Cretaceous (145 to 66 million years ago). The fossils of the adult oviraptor and the eggs with the embryos are dated to about 70 million years old. This is the first time researchers have found a non-bird dinosaur sitting on a nest of eggs that have been fossilized so that they still contain the babies inside!
The ~ 70 million year old fossil in question: an adult oviraptorid theropod dinosaur perched on top of a nest of its petrified eggs. Several eggs (including at least three containing embryos) are clearly visible, as are the forearms, pelvis, hind legs, and partial tail of the adult. (Shundong Bi, Indiana University of Pennsylvania)
What do the scientists say about the discovery?
Dr. Shundong Bi, of the Center for Vertebrate Evolutionary Biology, Institute of Paleontology, Yunnan University, China, Department of Biology, Indiana University of Pennsylvania, USA, and lead author of the study, told EurekAlert !, “Dinosaurs conserve on their nests, said rare, and so do fossil embryos. This is the first time that a non-bird dinosaur has been found sitting on a nest of eggs that preserve embryos, in a spectacular specimen. ‘
Although there are a few other examples of adult oviraptor on their nests with eggs, this is the first time that scientists have found embryos in the eggs. Study co-author, dr. Lamanna, a paleontologist at the Carnegie Museum of Natural History, USA, explains: ‘This kind of discovery, essentially petrified behavior, is the rarest of the rarest in dinosaurs. Although a few adult oviraptorides have been found in their eggs, no embryos have ever been found in the eggs. ‘
Dr. Xu, of the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, China, and one of the authors of the study, expects this rare discovery to contain a great deal of information: ‘It is extraordinary to think how much biological information is captured in just this single fossil . “Dr. Xu says, “We’ll be learning from this monster for many years to come.”
An attentive oviraptorous dinopaur dinosaur hatches its nest of blue-green eggs while its mate looks about 70 million years ago in what is now Jiangxi Province in southern China. ( Zhao Chuang )
The petrified eggs were about to hatch!
The scientists found an incomplete skeleton of an adult oviraptor with pebbles in its stomach. This is an example of gastrolyte, “Stomach stones”, which the creature digested to digest its food. It is also the first example of undisputed gastrolytes found in an oviraptoride, which the team says could help provide new information on the diet of these dinosaurs.
The dinosaur was found hunched over the nest of at least 24 petrified eggs, in a breeding or protective posture. This indicates that the dinosaur died while breeding or protecting its babies. But when the researchers used oxygen isotope analysis on the eggs, they found that it was incubated at high, bird-like temperatures, supporting the belief that the adult probably died while hatching its nest.
The partial skeleton of the oviraptorosaurus was found in a nest of at least 24 fossilized eggs. ( Bi et al., Science Bulletin, 2020 )
At least seven of the fossilized eggs still contain the remains of unbroken oviraptorous embryos. Based on the evolution of the embryos, the scientists think that some of the eggs were about to hatch. According to dr. Lamanna: “This dinosaur was a caring parent who eventually gave his life while raising his young.”
The article is published in Science Bulletin .
Top image: representation image of a baby dinosaur in an egg. Source: KtD / Adobe Stock
By Alicia McDermott