This fossilized Polycotylus latippinus, a carnivorous marine reptile that lived 78 million years ago, contains a smaller, less developed skeleton inside of her. Scientists are therefore speculating that this creature did not lay eggs like other dinosaurs, but gave birth to live young. If true, then this dinosaur may have exhibited maternal care behavior similar to modern marine mammals, such as dolphins. This fossil is on public display at the Natural History Museum of Los Angeles, so if you live in that area, you can get a close look for yourself.
Link -via reddit | Photo: Natural History Museum of Los Angeles Count