The mystery of how a gibbon became pregnant two years ago despite living alone in her cage in a Japan Zoo has finally been solved, according to Japanese zookeepers.

Pregnant Solitary Gibbon in a Japan Zoo

A 12-year-old white-handed gibbon named Momo shocked her zookeepers in February 2021 when she gave birth even though she had no known male companionship.

Momo is housed at the Kujukushima Zoo and Botanical Garden in Nagasaki,

Following a DNA test on her offspring two years later, the zoo has identified the father and even developed a theory on how the gibbons managed to interbreed.

A 34-year-old agile gibbon named Itō, who was in Momo's nearby enclosure when she became pregnant, was identified as the father by the test.

Mystery Solved

According to the zoo, Momo and Ito managed to mate through a tiny hole in a steel plate that separated their enclosures, the zoo told CNN on Friday.

The unnamed baby ape is now about 4.4 pounds and has been "growing healthily" with Momo's tender care, according to the zoo.

The hole was about 0.3 inches in diameter.

It is a precious life that is born into the world, according to the deputy director of the zoo, Hideki Hisano.

The zookeepers will continue to provide for the baby gibbon and pray for a long and healthy life for him.

Gibbons

The gibbon is one of the smallest apes, but despite their small size, they have loud voices that have evolved into complex languages and the ability to swing from branch to branch at up to 35 mph.

Several gibbon species are indigenous to parts of Asia.

This includes China, northeastern India, China, and the Borneo archipelago.

Due to human activities like deforestation, mining, and road construction, the number of agile gibbons in the wild has been declining, and they are now considered an endangered species by the International Union for Conservation of Nature.

Also Read: World's Most Endangered Species: 2 Young Javan Rhinos Seen in Indonesia National Park 

Other Mysterious Births

According to Live Science, there are other mysterious births in the animal kingdom.

Three Baby Zebra Sharks: Reef HQ Aquarium, Australia

At the Reef HQ Aquarium in Townsville, Australia, three baby zebra sharks were born in the month of April 2016.

Although animals giving birth in aquariums is not particularly uncommon, these youngsters were produced by a female shark named Leonie who, for several years, had been living away from male sharks.

In actuality, Leonie and her mate were split up in 2012.

Leonie may have been the first shark ever seen to transition from sexual to asexual reproduction, according to biologists at the time.

Parthenogenesis, a form of asexual reproduction that applies to Leonie, is when an embryo develops and matures without being fertilized by a male's sperm.

Instead, to "fertilize" the egg, an egg progenitor cell acts as a substitute for sperm.

Litter of Water Snakes: Cape Girardeau Conservation Nature Center, Missouri

At the Cape Girardeau Conservation Nature Center of the Missouri Department of Conservation (MDC), a female water snake gave birth to a litter of snakes in September 2015 without the aid of a male.

It was the snake's second consecutive "virgin birth," according to MDC officials, and she hadn't been with a male mate in eight years at the time, CNN Travel reported.

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