Experts at a US zoo are puzzled as to how an elderly ball python laid eggs despite not being near a male for over 15 years.
The 62-year-old snake laid seven eggs at St. Louis Zoo on July 23, which are expected to hatch in a month.
Mark Wanner, manager of herpetology at the zoo, said it's unusual but not rare for ball pythons to reproduce asexually.
Some mammals can store sperm for delayed fertilisation. In some cases, sperm may be stored from a few hours to several years.
The birth is also unusual because ball pythons usually stop laying eggs long before they reach their 60s, Wanner said.
"She'd definitely be the oldest snake we know of in history" to lay eggs.
Ball pythons, native to central and western Africa, are known to reproduce sexually and asexually, called facultative parthenogenesis, according to the Zoo's Facebook post.
Three of the eggs remain in an incubator, two of the eggs didn't survive, and the other two have been used for genetic sampling.
