Artist's reconstruction of Dinocephalosaurus showing the rough position of the embryo within the mother.IMAGE: DINGHUA YANG AND JUN LIUBirds do it. Crocodiles do it. Snakes do it. But Dinochepalosaurus don’t. According to an international team of researchers, the extinct marine reptile gave birth to live young, unlike the crocodiles and dinosaurs that count the species as an evolutionary ancestor. They published their analysis of a 245-million-year-old Dinochephalosaurus fossil unearthed in 2008 in China in Nature Communications yesterday (February 14).

Jun Liu, study coauthor and paleontologist from the Hefei University of Technology in China, told numerous news outlets that he initially thought the embryo found inside the 4-meter-long adult fossil might have been the remnants of the behemoths last meal.

“The embryo was curled,” coauthor Jun Liu, a, told National Geographic. “If an animal is ingested by something else, there’s no way to preserve that shape.”

Dinochephalosaurus is a member of archosauramorpha, a group that also included dinosaurs, birds, and crocodiles. The findings are the first evidence of a member of archosauramorpha giving birth to live young.