Researchers have discovered virgin births occurring in two types of wild species of snakes. Although virgin births, or facultative parthenogenesis, has been observed in many types of animals including chickens, sharks, lizards, and birds, it has never occurred with animals in captivity. These animals were kept away from males of their species, and the asexual birth was seen as an evolutionary necessity.
The strangest part of the virgin births is the frequency. It was found to occur 2.5 – 5% of the time in the wild, a number that is far more than just an evolutionary novelty. Although asexual birth is common in species like ants and aphids, researchers are still unsure why these virgin births occur so often in these snake species.