Scientists discover perfectly preserved embryo inside 66 million-year-old fossilised dinosaur egg

ITV News Reporter Yasmin Bodalbhai spoke to a researcher behind the discovery about why the finding is so significant

Scientists have discovered a rare, perfectly preserved embryo inside a fossilised dinosaur egg about to hatch from at least 66 million years ago.

The embryo, named ‘Baby Yingliang’, was found in the Late Cretaceous rocks of Ganzhou, in southern China, and belongs to a toothless theropod dinosaur, or oviraptorosaur.

Experts say it is one of the most complete dinosaur embryos ever found and helps shed a light on a key link between the behaviour of modern birds and dinosaurs.

Professor Steve Brusatte from the University of Edinburgh, part of the research team, said: “This dinosaur embryo inside its egg is one of the most beautiful fossils I have ever seen.

"This little prenatal dinosaur looks just like a baby bird curled in its egg, which is yet more evidence that many features characteristic of today’s birds first evolved in their dinosaur ancestors.”

Scientists from the University of Birmingham and China University of Geosciences in Beijing found the posture of ‘Baby Yingliang’ unique among known dinosaur embryos - its head lies below the body, with the feet on either side and the back curled along the blunt end of the egg.

In modern birds, this posture - called 'tucking' and previously unrecognised in dinosaurs - sees the embryo bend their body and bring their head under their wing shortly before hatching so they can prepare to crack the egg.

It is one of the best-preserved dinosaur embryos ever reported Credit: Xing et al., 2021

Embryos that fail to attain this posture are more likely to die because they cannot hatch properly.

After studying the egg and embryo, researchers believe that such pre-hatching behaviour, previously considered unique to birds, may have originated among non-avian theropod dinosaurs.

Fion Waisum Ma, joint first author and PhD researcher at the University of Birmingham, said: “Dinosaur embryos are some of the rarest fossils and most of them are incomplete with the bones dislocated.

"We are very excited about the discovery of 'Baby Yingliang' - it is preserved in a great condition and helps us answer a lot of questions about dinosaur growth and reproduction with it.

An artist's reconstruction of a baby oviraptorid dinosaur in the egg nest Credit: Julius Csotonyi

“It is interesting to see this dinosaur embryo and a chicken embryo pose in a similar way inside the egg, which possibly indicates similar prehatching behaviours.”

The embryo, housed in Yingliang Stone Nature History Museum, is around 27cm long from head to tail and lies inside a 17-cm-long elongatoolithid egg.

Baby Yingliang was identified as an oviraptorosaur due to its deep, toothless skull. Oviraptorosaurs are a group of feathered theropod dinosaurs, closely related to modern-day birds, known from the Cretaceous of Asia and North America.