Zoo Solves Mystery Of How An Ape Got Pregnant By Herself

An ape in a Japanese zoo got pregnant through her male neighbor discovering a hole in the fence between them that was just the right size.

By TeeJay Small | Updated

planet of the apes 4

After more than two years of wondering whether or not an ape in a Japanese zoo had conceived immaculately, zookeepers seem to think they’ve finally pieced together the mystery of the monkey. Momo, a 12-year-old white-handed gibbon became pregnant back in 2021, despite never interacting with other apes of her kind. According to a write-up in Gizmodo, the answer lies in a small hole in the wall, which a fellow ape used to copulate with Momo.

The supposed “glory hole” was located on a hatch used to separate Momo’s cage from the ape exhibit, where a 34-year-old gibbon named Itoh seized the opportunity to get busy when nobody was watching. The employees of the Kujukushima Zoo & Botanical Garden in Nagasaki were scratching their heads for years trying to piece this mystery together, as no security footage was available to capture the interaction either. Itoh’s fatherhood was confirmed via DNA sampling which proved that he was in fact the father, Maury Povich style.

The superintendent of the Nagasaki zoo, Jun Yamano, explained that the DNA test took years to conduct due to Momo’s highly protective nature over the mystery child ape, preventing scientists from getting close enough to collect samples. Eventually, hair and stool samples were collected from the baby as well as each of the potential male suitors, and Itoh was a match. Once the zoo found out that Itoh was the father, the rest of the mystery seemed to finally fall into place, like Glass Onion‘s detective Benoit piecing together the makings of a high-profile murder case.

A pair of white-handed gibbons

In fact, it took over six months following the birth of the unnamed ape child to even properly discover its sex, as Momo was so attached to her baby she wouldn’t even let zookeepers inspect him. The large zoo holds a wide array of exhibits and is often booked for reservations several days in advance, leaving the animal handlers with plenty of other responsibilities on their plate in the meantime. As the young ape continues to get a bit older, he gains more independence from his mother, allowing the requisite hair samples to be collected.

Apes such as Momo and Itoh are generally separated in order to avoid procreation in captivity in this way, as it can often be dangerous for their kind to mate under these conditions. Zookeepers had previously assumed that the holes in the partition were not large enough for such an event to take place, not bothering to conceal the wooden plank with additional locking mechanisms due to the unlikelihood of such an event. Of course, Momo turned out to be an exceptionally caring mother to her mysterious baby, despite handlers not being aware she was pregnant until seven months into her term.

White-handed gibbons are considered an endangered species, so perhaps the secretive rendezvous should be encouraged, breeding the species’ numbers back into the green zone. Apes of this variety also tend to live in family units, so perhaps the zoo owners will consider allowing Itoh and Momo to reunite as a family, provided the two are interested in more than just a one-night stand.