Ancient Python Lays Eggs, Apparently Without Male Help
The snake, which is about 62 and hasn’t had contact with a male python in at least 15 years, surprised zookeepers at the St. Louis Zoo.
It’s been about two months since zookeepers at the St. Louis Zoo found a ball python believed to be about 62 years old coiled around a clutch of seven eggs she had laid. But the surprise has not worn off.
Not only had the snake not had contact with a male python for at least 15 years; it also had already outlived its life expectancy by more than two decades.
It’s rare but not impossible for ball pythons, one of the smallest python species, to reproduce asexually. But Mark Wanner, zoological manager of herpetology at the St. Louis Zoo, said that snakes typically live only about 30 or 40 years. It’s “kind of crazy” the python made it past 60, he said, let alone laid eggs.
“It’s not normal to see a snake live to that age,” he said. The oldest snake ever documented in a zoo was a 47-year-old ball python at the Philadelphia Zoo, Mr. Wanner said, making the St. Louis Zoo’s python now the oldest snake ever recorded. “That makes it even more incredible that she laid a clutch of eggs.”
Two of the eggs, which she laid on July 23, are being used for genetic sampling, which will help determine whether the python reproduced sexually or asexually. Snakes are also known to store sperm from an earlier encounter for delayed fertilization, though Mr. Wanner said that was unlikely in this case, as the longest snake sperm storage documented was seven years.
Of the remaining eggs, three are in an incubator at the zoo’s herpetarium, which houses its snakes, lizards, frogs and other amphibians. The two others did not survive.
Dr. Jonathan Losos, a professor of evolutionary biology at Washington University in St. Louis who specializes in reptiles, said scientists had known for a while that there were some species of snakes and lizards in which no males exist and females reproduce asexually.
“What we didn’t realize until relatively recently is that there are some species who normally are sexual — that is, require a male and a female to reproduce — that can occasionally reproduce without any sperm,” Dr. Losos said. Komodo dragons, for instance, have been known to lay eggs asexually, a process called facultative parthenogenesis.
The ball python in St. Louis, which is between four and four and a half feet long and does not have a name, arrived at the zoo in 1961 through a private owner. It was estimated to be about 3 years old at the time. The zoo also has a male ball python that is about 31 years old. They are kept side by side in the zoo’s herpetarium, out of public view, but never come into contact.
https://www.nytimes.com/2020/09/12/us/st-louis-zoo-62-year-old-python.html
Snakes are so fascinating. I was mowing along the edge of our woods on Sunday, and saw a beautiful little bright green garter snake, about 2 ft. long, sunning himself on a branch. Unfortunately, I did not see him when I came back through, and he was cut in many pieces.
