Sun Bears Eat With Their Tongues. 25cm of Them.

The sun bear, Helarctos malayanus, is the smallest bear on Earth and almost certainly the least famous. It lives in the lowland tropical forests of Southeast Asia, weighs between 25 and 65 kilograms, and has a tongue that extends up to 25 centimeters from its mouth. That tongue is the central tool of its existence.

Sun bears eat honey, bee larvae, termites, and beetle grubs extracted from inside trees and underground nests. The tongue reaches places no other bear’s tongue can reach, probing deep into termite mounds, bee nests, and rotting wood to extract food that other animals cannot access. The bear’s powerful curved claws tear open the substrate, and the tongue does the rest.

The chest patch that gives the sun bear its name, a pale crescent of fur on an otherwise black coat, varies between individuals in shape and size. No two are identical, in the same way that no two human fingerprints are identical. Wong Siew Te at the Bornean Sun Bear Conservation Centre in Sabah, Malaysia, has used these chest patches to identify individual bears in camera trap surveys, building population data for a species that is genuinely difficult to study in dense forest.

The Face

Sun bears have unusually mobile, expressive faces for bears, with facial musculature that allows a range of expressions that other bear species cannot produce. In 2024, a study published in Scientific Reports documented sun bears mimicking the facial expressions of other sun bears during play, producing accurate copies of expressions within half a second of seeing them. This kind of rapid facial mimicry had previously been documented only in humans and other great apes, and its presence in sun bears suggests that the capacity evolved independently in a lineage that diverged from the primate lineage over 90 million years ago.

The function of facial mimicry in sun bears appears to be social communication during play, signaling non-aggressive intent and maintaining the interaction. A bear that mirrors your expression is telling you it is still playing. The signal is the same one humans use. The evolutionary path to it was completely different.

Deforestation and the Palm Oil Problem

Sun bears are listed as Vulnerable on the IUCN Red List, with populations declining across their range due to deforestation, primarily for palm oil plantations. Borneo and Sumatra, which together hold the largest remaining sun bear populations, have lost over half their forest cover in the past 50 years. The bears that remain are increasingly confined to forest fragments surrounded by agricultural land, where they come into conflict with humans when they raid crops or beehives.

The sun bear that can mirror your facial expression, that carries a tongue a quarter of a meter long, that has a chest patch as unique as a fingerprint, is being displaced by a crop whose oil appears in roughly half of all packaged food products sold globally. The connection between a supermarket shelf and a disappearing bear is real, direct, and almost never discussed.

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