Thelma, a yellow-bellied water snake from Missouri, has astonished the world after giving birth for the second time in just two years, despite the fact it has never had sex with a mate. The snake has spent all of the eight years it has been in captivity without access to males, meaning that it shouldn’t be able to reproduce, but experts believe a rare occurrence known as parthenogenesis may be to blame.
Parthenogenesis is a strange form of asexual reproduction that is common in arthropods. However, it can also occur in some other types of animals such as amphibians, reptiles and birds, although it is generally very infrequent. The process sees an unfertilized egg develop into an embryo when certain cells fuse with it and trigger the cells to begin to divide.
Although the new snakes didn’t survive, those born previously are currently on display at the Cape Girardeau Conservation Nature Center along with their mother. “This is the way you make discoveries when you keep things in captivity. You learn things about what they’re capable of,” said AJ Hendershoot, an employee at the center.