A team of investigatorss has succeeded in describing embryos between 72 and 66 million years old “beautifully preserved” in dinosaur egg fossils, which highlights the relationship between the behavior of modern birds and these extinct animals.

Embryo, nicknamed “Bebe Yingliang”, found in Ganzhou, di from China, and I belongand toothless theropod dinosaurs or ovirraptorosaurs; fossils show that this dinosaur developed a posture similar to that of a nearly hatched bird.

Scientists discovered that the posture of Baby Yingliang, one of the most complete dinosaur embryos ever found, was unique: your head is under your body, with your feet on either side and your back curled up along the blunt end of the egg.

This posture, hitherto unknown in dinosaurs, similar to modern bird embryos, according to a statement from the University of Birmingham (UK).

Until now, this posture was exclusive to birds.

In birds, this posture related to behavior controlled by the central nervous system and is fundamental to hatching success.

After studying eggs and embryos, the researchers believe that this behavior before hatching, which until now considered exclusively for birds, may originate between non-avian theropods.

Led by experts from University of Birmingham and China University of Geosciences (Beijing), the team, which also consisted of scientists from Canada, published the details in the journal iScience.

The forgotten fossil in the box

The embryo was articulated without major changes due to fossilization: with an approximate length of 27 centimeters from head to tail, the creature is inside a 17 centimeter egg.

According to the magazine, specimen obtained in 2000 by Liang Liu, the director of a company called Yingliang Group, who suspects it may contain fossilized eggs.

But it ends up in storage mostly forgotten until about ten years later, when, during the construction of the Yingliang Stone Natural History Museum, staff sorting boxes and excavating fossils; now is where you are.

The relationship between dinosaurs and chickens

“We are very pleased with the discovery of Baby Yingliang because it has been preserved in good condition and help us answer many questions about dinosaur growth and reproduction“, said Fion Waisum Ma.

“It’s interesting to see that this dinosaur embryo and chicken embryo have the same pose inside the egg, maybe show similar behavior before hatching“.

Yingliang baby identified as ovirraptorosaurus based on its deep, toothless skull; This was a group of feathered theropod dinosaurs, closely related to modern birds, known from Cretaceous Asia and North America.

Theropod dinosaur evolution

Birds are known to thrive a series of tuck-in poses, where the body is bent and the head is tucked under the brim just before hatching. Embryos that do not reach this position are more likely to die because they were not born.

Comparing Baby Yingliang to other people’s embryoss theropods, long-necked sauropod dinosaurs and birds, the team proposed that recoiling behavior, thought to be unique to birds, first evolved in theropod dinosaurs tens or hundreds of millions of years ago.

Additional discoveries of embryonic fossils it would be invaluable to further test this hypothesis, conclude the researchers.