Sea monsters made great mothers
Fossil plesiosaur had a baby on board
By Nadia Drake
The fossil of a pregnant plesiosaur who died 78 million years ago indicates that the ancient sea monsters were surprisingly like today’s marine mammals.
The aquatic, carnivorous reptiles gave birth to live young, scientists report August 12 in Science. And they probably birthed just one plesio-baby at a time – one very big baby, estimated to be more than 40 percent of the mother’s body length at birth. Putting so much effort into a single offspring suggests that like today’s marine mammals, plesiosaurs offered a bit of postnatal maternal care.
“If you’re going to put all your eggs in one basket, then you’re going to want to take care of that egg when it comes out,” says paleobiologist F. Robin O’Keefe of Marshall University in Huntington, W.Va.