The Mystery of Virgin Births in Crocodiles and Dinosaurs Unveiled

A female crocodile living alone in a Costa Rican zoo laid a clutch of eggs, one of which yielded a stillborn baby crocodile that was a parthenogen, the product of a virgin birth containing only genetic material from its mother. This is the first time parthenogenesis has been found in crocodiles, and it suggests that pterosaurs and dinosaurs might also have been capable of such reproductive feats. Parthenogenesis is not necessarily a response to stress or a lack of mates, and it is possible that it is simply a trait that doesn’t have enough downsides for evolution to weed it out.