Bornean Gibbon

• Common Names: Borneo Gibbon, Müller’s Gibbon, Gary Gibbon
• Taxonomy Classification Year: 1841
• Monkey Size: 44 to 64 cm (17 to 25 in)
• Skin Color(s): Light brown
• Habitat: Forest, rainforest
• Diet: Herbivorous
• Native Countries: Indonesia, Malaysia, Brunei

Also known as the Müller’s or gray gibbon, the Bornean gibbon^[1] is native to the Bornean Island, which is divided between the nations of Brunei, Malaysia, and Indonesia.

• They have light brown fur that fades to black on the face, chest, and inner arms, with a white border around the face.
• They have padded buttocks and pronounced canines, and the base of the thumb unusually starts at the wrist rather than the typical palm of the hand, enabling them a wide range of motion.
• However, this limits their ability to grasp small objects. One of their most distinctive features is their incredibly long arms, especially their long ulna and forearms’ radial bones.
• This trait, along with many other minor skeletal adaptations, tailors the species to its method of locomotion: brachiation.

The Borneo gibbon diet includes Jointfir (Gnetum), Breadfruit (Artocarpus) and Mangoes (Mangifera)^[¶].

• ​Although every Borneo gibbon song sounds similar to a human, they are very individual. Computer analysis can identify individual female species from their songs with an accuracy of 95.7%.
• These primates are very territorial. Their range averages 34 ha (84 acres), and around 75% of this area is actively defended.
• Usually, Borneo gibbons live in groups of 3 or 4, a pair and their young.
• They are active between 8 and 10 hours a day. They are diurnal, waking up just before sunrise and falling asleep at night before sunset.
• Borneo gibbons spend little time socializing: they spend only around 5 percent of their day grooming and socializing, which is considerably low for a primate species.