Perfectly Preserved Dinosaur Embryo Found Inside Fossilized Egg

[Judi Lynn]

The 66- to 72-million-year-old specimen is one of the most complete dinosaur embryos ever found.
author
BEN TAUB

An incredibly rare, fully articulated dinosaur embryo has been found inside a fossilized egg that had been collecting dust for over a decade in the storage room of a museum in China. Thought to be between 66 and 72 million years old, the unborn specimen reveals an incredible link between dinosaurs and modern birds.

Belonging to a group of feathered, toothless theropods known as oviraptorosaurs, the unhatched creature is estimated to be about 27 centimeters (10.6 inches) long, and marks the first discovery of a dinosaur embryo displaying a posture that is typical of present-day bird embryos. Shortly before hatching, modern birds engage in a series of maneuvers known as tucking, which involves curving the body and bringing the head down under the wing, yet the evolutionary origins of this behavior have until now remained unknown.

Reporting their discovery in a 2021 paper, the study authors explain that their specimen – nicknamed Baby Yingliang – was found with its head “ventral to the body, with the feet on either side, and the back curled along the blunt pole of the egg.” Such a posture, they say, is “previously unrecognized in a non-avian dinosaur, but reminiscent of a late-stage modern bird embryo.”

Tucking is thought to play a vital role in the hatching process of birds, and those that fail to adopt this position are much less likely to survive their escape from the egg. That Baby Yingliang appears to have adopted the same pose suggests that the phenomenon may have first evolved among the ancient theropod ancestors of modern birds.

More:
https://www.iflscience.com/perfectly-preserved-dinosaur-embryo-found-inside-fossilized-egg-72164