Scientists announced on Tuesday discovery of a perfectly preserved dinosaur embryo that dates back at least 66 million years ago and that was preparing to hatch.
The fossil was found in Ganzhou, southern China, and belongs to a denture-less theropod dinosaur, which scientists have called “baby Yingliang.”
Species of dinosaur with exotic nose discovered in England
“It’s one of the best dinosaur embryos ever found,” University of Birmingham researcher Fion Waisum Ma, who co-authored the publication in the journal iScience, told AFP.
Ma and his colleagues found the embryo with its head tucked under its body, feet on both sides, and its back curved, a posture that has not been seen before in dinosaurs but is similar to that of modern birds.
In birds, this behavior is controlled by the central nervous system and is called “folding”. Chicks preparing to hatch put their head under the right wing to keep it stable while breaking the shell with their beak.
Embryos that fail to perform this position are more at risk of dying from a failed hatch.
“This indicates that such behavior in modern birds first evolved among dinosaurs, their ancestors,” said Ma.
An alternative to this folding could be similar to what modern crocodiles do. They position themselves as if they were seated, with their head bent towards their chest, to hatch.
Were feathery dinosaurs that lived in what is now Asia and North America during the Late Cretaceous period.
They had various types of beaks and diets, and their size varied between that of a modern turkey and that of a huge gigantoraptor, eight meters long.
The “Yingliang baby” is 27 centi-meters long from head to tail and is found inside a 17 centi-meter egg at the Yingliang Stone Nature History Museum.
Researchers believe the creature is between 66 and 72 million years old and could probably be preserved when the egg was buried as a result of a flood, protecting it from carrion animals for so long.
It would have grown to two or three meters in length if it reached adulthood and would likely have fed on plants.
The specimen is one of several egg fossils that have been forgotten in a deposit for decades.
The team of scientists suspected they might contain unborn dinosaurs and scraped off part of the egg to find the embryo inside.
“This dinosaur embryo inside this egg is one of the most beautiful fossils I’ve ever seen,” University of Edinburgh professor Steve Brusatte and member of the research team said in a statement.
“This little dinosaur in its prenatal state is very similar to a baby bird curled up in its egg, which provides further evidence that many of the characteristics of today’s birds evolved from their dinosaur ancestors,” he continued.
Scientists hope to study “baby Yingliang” in more detail using advanced scanning techniques to map its entire skeleton, including the skull bones, because part of its body is still covered in rock.