It’s been a widely accepted fact that reptiles lay eggs. But did they always? New findings in a pleiosaurs’ fossil revealed that this marine reptile gave birth to live young. Via New Scientist:
Think less sea monsters, more doting parents: the long-necked plesiosaurs that roamed the seas during the dinosaur era gave birth to live young. They probably cared for their offspring and may even have lived in large social groups, like modern-day whales.
Plesiosaurs were reptiles, which as a group tend to lay eggs rather than giving birth. Other prehistoric marine reptiles were known to be exceptions to that rule, but until now fossil evidence that plesiosaurs did the same has been frustratingly elusive. “People have looked and looked,” says F. Robin O’Keefe of Marshall University in Huntington, West Virginia.
Last year O’Keefe was called in to help prepare a fossil plesiosaur for display in the Natural History Museum of Los Angeles County. Originally excavated by a Kansas family on their ranch in 1987, it had sat in the museum basement ever since, until Luis Chiappe, director of the museum’s dinosaur institute, decided to take a closer look.
[Continues at New Scientist]