A fossilized dinosaur egg unearthed in southern China has revealed one of the most complete dinosaur embryos ever discovered, providing paleontologists with unprecedented insight into the origins of behaviors now associated with modern birds. Named Baby Yingliang, the specimen was found inside a 17-centimeter egg and is believed to be between 66 and 72 million years old. It had been stored in a museum warehouse for over a decade before a staff member noticed bones visible through a crack in the shell.
The discovery was made at the Yingliang Stone Natural History Museum in Nan’an, a city in China’s Fujian Province. The embryo, identified as an oviraptorosaur—a group of feathered theropods closely related to birds—is curled up inside the egg in a position that scientists say mirrors the “tucking” posture seen in bird embryos shortly before hatching. The fossil’s excellent preservation allowed researchers to study this posture in detail, marking a first for non-avian dinosaurs.
Hidden for Years, Then a Breakthrough
The egg had been part of a collection donated to the museum in 2000, likely uncovered during construction work in the Shahe Industrial Park area of Ganzhou City, Jiangxi Province. It was not examined until 2015, when museum staff noted its unusual features. “The museum realized it must be an important specimen, so they contacted us to look at the egg,” said Waisum Ma, a paleontologist at the University of Birmingham in the United Kingdom. “We were surprised to see this embryo beautifully preserved inside.”
The embryo’s posture, with its head tucked ventrally to the body and feet positioned on either side, closely resembles the position assumed by bird embryos preparing to hatch. This behavior, known as tucking, is controlled by the central nervous system and is considered essential for a successful hatching. According to researchers, the specimen is the first non-avian dinosaur embryo found with such a posture, suggesting the behavior may have originated in theropod dinosaurs rather than birds.
Bird-Like Behavior, Millions of Years Before Birds
The oviraptorosaur embryo, about 27 centimeters long, exhibits a level of articulation rarely seen in fossilized dinosaur embryos. According to a 2021 study co-authored by Chinese paleontologist Xing Lida and published in iScience, the embryo’s positioning had not been previously recognized in dinosaurs. The authors describe the posture as “reminiscent of a late-stage modern bird embryo.” They also note that many modern birds that fail to assume the tucking position are less likely to survive hatching, underlining the importance of this behavior.
“This little prenatal dinosaur looks just like a baby bird curled in its egg,” said Steve Brusatte, a paleontologist at the University of Edinburgh and co-author of the study. “Which is yet more evidence that many features characteristic of today’s birds first evolved in their dinosaur ancestors.” While other oviraptorid embryos have been studied before, Baby Yingliang is by far the most complete and informative, providing an unusually clear view of dinosaur development.
A Fossil Rarity with Far-Reaching Implications
Researchers say the egg’s exceptional preservation may be due to rapid burial in sediment, possibly by sand or mud, shortly after it was laid. While the origins of the egg remain somewhat unclear, the site in Ganzhou City has yielded multiple oviraptorid fossils in the past, making it a significant location for understanding Late Cretaceous biodiversity in East Asia.
Despite the find’s importance, scientists stress that one specimen is not enough to draw definitive conclusions. “It is very rare to find dinosaur embryos, especially ones that are intact,” said Ma. The team acknowledges that more examples are needed to determine whether the observed posture was widespread among theropods or specific to oviraptorosaurs. Still, the discovery suggests that behaviors often thought to be uniquely avian may have emerged far earlier than previously assumed.
Baby Yingliang is now housed at the Yingliang Stone Natural History Museum, where it remains under further examination.
Don’t be foolish, just someone’s theory. 70 million years?
The figures that these people produce have no true scientific value as there is no evidence to back them up.
They are just theories, not to be believed.
This is no more than around 8 thousand years old.
Bruce boy here just asserts that these are just theories, then gives his own crackpot theory that these are just 8 thousand years old. An honest person would tell you to go and find out yourself. Educate yourself on the scientific process. Do that and not listen to Brucey boy here make unfounded assertions, which he ironically hates.
I believe it to be true. I have a couple of dinosaur eggs I believe. A month ago I dropped one on accident and inside was a bird I believe it to be a terridactal