Photo: Courtesy of Xing Lida

A dinosaur embryo perfectly preserved inside a fossil egg, the most complete specimen ever recorded in scientific studies, was found in China according to research by an international team of scientists. 

The dinosaur embryo was discovered in rock strata of the Late Cretaceous in a site in Ganzhou, in East China's Jiangxi Province, and is now in the Yingliang Stone Natural History Museum in East China's Fujian Province. 

The research team made up of scientists from institutions in China, the UK and Canada conducted the research that was published on the iScience magazine on December 22.

The museum nicknamed the specimen Yingliangbeibei. The dinosaur embryo was preserved in a fairly primitive state, undisturbed by fossilization, and shows a clear picture of what it would have been like when it lived. The total length of the embryo is 27 centimeters and curls inside a 17-centimeter-long fossil egg. 

Yingliangbeibei was identified as a specimen of Oviraptorsauria which is a kind of theropod covered with feathers. They lived in the Cretaceous period in Asia and North America and are closely related to modern birds. 

Its preservation position is unique among known dinosaur embryos with its head kept under its body, its feet at its sides and its back is curled up along the blunt end of the egg. This posture is similar to that of a modern birds and has never been seen in a dinosaur embryo fossil before. 

By comparing Yingliangbeibei with embryos from other theropods, long-necked sauropods, and birds, the research team suggests that contractions, thought to be unique to birds, may have first evolved in theropod dinosaurs tens or even hundreds of millions of years ago. The discovery of more fossilized embryos is extremely important to further test this hypothesis. 

Ma Huixin, first co-author of the research paper, noted that dinosaur embryo fossils are among the rarest fossils and most of them are poorly preserved with bones dislocated. "We can answer a lot of questions about dinosaur growth and reproduction," Ma said, adding that the postures of the dinosaur embryo and the chicken embryo inside the egg may indicate a similar behavior before hatching. 

According to Xing Lida, associate professor from the China University of Geosciences and co-author of the research, the fossil egg was collected by Liu Liang, President of Yingliang Group, in 2000.