The Philippine tarsier is a tiny, nocturnal primate with eyes larger than its brain.

Nature · Published 30 September 2026 · Updated 25 October 2026 Swipe more like this →

In short: With eyes that cannot move in their sockets, this fist-sized primate relies on a rotating head to scan the forest. It is a master of the leap, using elongated ankle bones to launch itself between trees, while its adhesive-padded fingers ensure it never loses its grip on the canopy.

The Philippine tarsier, or Carlito syrichta, belongs to the Tarsiidae family, a lineage estimated to be 45 million years old. While once grouped with all other tarsiers in the genus Tarsius, taxonomic revisions—most notably by Shekelle and Groves in 2010—placed the Philippine species into its own genus, Carlito. This name honors Filipino conservationist Carlito Pizarras. These primates are endemic to the southeastern Philippine archipelago, with established populations on islands including Bohol, Samar, Leyte, and Mindanao.

Physically, the tarsier is defined by extreme adaptations for a nocturnal, carnivorous lifestyle. Its eyes are disproportionately large, boasting the highest eye-to-body weight ratio of any mammal. Because these eyes are fixed in the skull, the animal compensates with a neck structure that allows its head to rotate 180 degrees. Its name derives from its elongated tarsus, or ankle bone, which acts as a spring for leaping up to three meters between trees. Unlike lemurs, tarsiers possess a dry, hair-covered nose, placing them in the same suborder as monkeys, apes, and humans.

Tarsiers are the only entirely carnivorous primates, feeding on insects, spiders, and small vertebrates like lizards. They live in monogamous pairs, communicating through high-pitched vocalizations that serve to defend their territory. Despite their specialized nature, they face significant threats from human settlement and habitat loss. Their survival remains precarious, as they require specific environments like secondary forests and dense vegetation to thrive, often perching just two meters above the ground to hunt and rest.

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