Thelma 's virgin births surprised her keepers Thelma 's virgin births surprised her keepers Initially, a virgin birth, also known as parthenogenesis, was thought to be triggered by extreme situations; it was only documented among captive animals, for example, perhaps by the stress, or isolation. Why among vertebrates, can fish, reptiles and birds have virgin births, but mammals, including humans, seemingly cannot? Even here, things aren 't straightforward Virgin turkeys Perhaps the best understood 'virgin ' vertebrate is the common domesticated turkey. Flora, a virgin Komodo dragon that gave birth Komodo dragons are also capable of virgin births Then in recent years, scientists have also documented different snake species, including boas