More than 66 million years ago, a fossilized dinosaur egg was discovered to contain an embryo, and international researchers believe the discovery establishes a link between dinosaurs and current birds.
The fossilized dinosaur egg was discovered in 2000 by Yingliang Group, a stone mining company in Ganzhou, Jiangxi Province, southern China. They were stored because company employees felt they were potentially dinosaur fossils.
It was not until the corporation began constructing the Yingliang Stone Nature History Museum in 2010 that museum personnel discovered the fossils while sorting through storage and spotting bones within the egg. After examining the fossils, scientists found that one of the eggs contained an embryo they dubbed "Baby Yingliang."
Their research was published Tuesday in the peer-reviewed journal iScience.
"Dinosaur embryos are extremely rare, and the majority of them are incomplete, with bones displaced. We are overjoyed to have discovered 'Baby Yingliang.' "According to a statement from Fion Waisum Ma, the study's author and a researcher at the University of Birmingham in England. "It is preserved in a great condition and helps us answer a lot of questions about dinosaur growth and reproduction with it."
Oviraptorosaurs are closely related to birds and are classified as therapods. Therapods, like other members of the group, such as Tyrannosaurus rex and velociraptor, was predatory dinosaurs with short forelimbs that moved on two feet.
However, scientists found that the embryo shared a very similar stance to birds before hatching, which is regarded as unique in the animal kingdom.
According to researchers, the oviraptorosaurs embryo was in a tucking position, with its feet on the side of its head and its back against the shell. Today, birds are expected to remain in this position before hatching; if they do not, they have a greater likelihood of dying before or during delivery.
The dinosaur's lack of flight was the first time the tucking position was observed in a non-avian species. The findings imply that present bird hatching methods evolved hundreds of millions of years ago from non-flying dinosaurs. The embryo is believed to be between 66 and 72 million years old.
"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," Waisum Ma said. "This posture had not been recognised in non-avian dinosaurs before."
The embryo will be further evaluated to understand its anatomy better, learn more about dinosaur embryos, and learn more about the relationship between dinosaurs and modern birds.
"This dinosaur embryo inside its egg is one of the most beautiful fossils I have ever seen," said co-author and paleontologist Steve Brusatte of the University of Edinburgh in Scotland.
"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."
