Crocodile has first-ever 'virgin birth' in isolation.

An 18-year-old American crocodile in a Costa Rican zoo impregnated herself through a form of asexual reproduction called facultative parthenogenesis, according to research published Wednesday. While other animals have reproduced through parthenogenesis, it was the first known case involving a crocodile. The stillborn crocodile was a genetic match solely to its mother, meaning that the adult crocodile impregnated herself. The International Union for Conservation of Nature lists American crocodiles as a vulnerable species.