October 24th marks International Gibbon Day. The special day is all about the adorable lesser apes, who are also called "jungle acrobats" because of their superb mobility. Did you know that they are excellent singers too? 

There are a total of 18 species of gibbons, all endemic to southern Asia. China has seven of them, including a new species, the Skywalker hoolock gibbon, which was first described in 2017. Several gibbon species are named after Chinese provinces like Yunnan and Hainan. 

As the only member of the lesser ape, the gibbon is more similar to monkeys than great apes (orangutans, gorillas, chimpanzees, and humans). The most distinctive difference between apes and monkeys is the tail. The gibbon, like all other apes, has no tail. But do not worry about how it keeps balance on the tree: The gibbon is a fantastic athlete and acrobat. 

The gibbon moves in the jungle by swinging from branch to branch for distances of up to 15 meters at 55 km/h. It can also make leaps of up to eight meters, and walk with their arms raised for balance. In fact, the gibbon is the fastest and most agile of all tree-dwelling, nonflying mammals.

The coolest thing about the gibbon is that it can sing. Though it stands at only half of a man's height, its voice can be louder than any man. Gibbon songs can be heard from as far as one kilometer away. Gibbon couples sing a duet to form family bonds, while single gibbons sing to attract their Mr or Mrs Right. Each species of gibbon, or even each group of them, has specific songs. 

Ancient Chinese poets loved the gibbon songs, believing the songs brought up nostalgia and complex feelings. The gibbons used to inhabit a wider area in central China, but their habitats have now shrunk to just the south. 

According to the IUCN Red List of Threatened Species, almost all gibbon species are endangered, and four of them are assessed as "critically endangered" due to degradation or loss of their forest habitats. Luckily, the environment in China is improving to ensure a safe home for the apes. Many volunteers are also working to rescue these terrific singers too. 

(Cover image via VCG)

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