This 2015 photo provided by the Missouri Department of Conservation shows a female yellow-bellied water snake at the Cape Girardeau, Mo., Conservation Nature Center that for the second time in two years has given birth without any help from a male member of the species, conservationists say. The offspring did not survive this summer, but they did in 2014. It is believed to be the first documented cases in the species of parthenogenesis, or asexual reproduction. (Candice Davis/Missouri Department of Conservation via AP)