Pongo – Orangutans

Considered one species until 1996, when a second species were identified. A third was described in 2017!

Sharing a common ancestor with humans that lived nearly 10-12 million years ago, orangutans have diverged significantly both morphologically and behaviorally, leading to a distinct branch of the evolutionary tree. Their place within the hominid family and other great apes underscores their importance in understanding primate evolution and our origins.

Orangutans exhibit remarkable adaptations suited to their predominantly arboreal lifestyle. They are designed for a life spent in the trees, with physical characteristics that enable them to easily navigate the forest canopy. Their long forelimbs, complemented by hook-like hands and curved fingers, allow for efficient swinging from branch to branch, a mode of locomotion known as brachiation.

Their hindlimbs, although shorter, possess hand-like feet that are equally adept at grasping and holding, enabling orangutans to hang securely from tree branches while foraging for fruits, leaves, and bark, which constitute the bulk of their diet. The significant sexual dimorphism observed in orangutans, particularly among adult males who develop distinctive cheek pads and a throat pouch for enhanced vocalizations, further highlights the diversity within their species.

Unlike the more social African apes, orangutans are known for their solitary nature, with adult males and females typically coming together only for mating. Despite this, they exhibit complex social behaviors, including mother-offspring bonds that last many years, during which time the young learn essential survival skills from their mothers. Communication among orangutans involves a variety of vocalizations, gestures, and facial expressions, indicating a rich emotional and cognitive life.

Orangutans are currently facing a critical threat from habitat destruction due to logging, palm oil plantations, and human encroachment, which has led to significant population declines. All three species of orangutans, the Bornean (Pongo pygmaeus) and Sumatran (Pongo abelii), and Tapanuli orangutan (Pongo tapanuliensis) are classified as Critically Endangered.