Turns out, there’s at least one yellow-bellied water snake that doesn’t need a man. In September 2015, a female water snake at the Missouri Department of Conservation’s (MDC) Cape Girardeau Conservation Nature Center gave birth to a litter of snakes without any help from a male. At the time, the snake had not been with a male mate in eight years, and it was actually the second year in a row that she had a “virgin birth,” according to MDC officials.
The female snake’s impressive feat boils down to parthenogenesis, during which babies are produced by females absent of genetic contribution from a male. Scientists have seen this type of reproduction in other snake species, including copperheads, green anacondas and pit vipers.
With parthenogenesis, the normal division of cells typically results in four egg-progenitor cells, but instead of the female’s body reabsorbing three egg-progenitor cells (leaving one egg), one of the female cells behaves like sperm and fertilizes the egg. Why does this happen? Essentially, this type of asexual reproduction occurs when there is a lack of suitable mates. It’s evolution in action, folks. [Read the full story about the snake’s virgin birth]