Aye-aye

The largest nocturnal primate, a dark, shaggy lemur found only in Madagascar, with front teeth that grow throughout life like a rodent's. It taps along a branch with a thin middle finger, up to about eight times a second, gnaws into the hollow it detects and hooks out the larva inside.

• The tapping finger has a ball-and-socket joint at its base, giving it an unusually wide range of movement.
• It was first classified as a rodent, and is now the only living member of its own lemur family.
• A small extra digit of bone and cartilage, a pseudothumb, was described on its wrist in 2019.
• Females have two nipples set low on the abdomen, an unusual position for a primate.
• It bites through the shells of coconuts and hard forest nuts and scoops out the contents with a finger.

Aye-ayes are nocturnal, nesting in tree shelters by day and tapping, listening, and extracting food after dark.

Habitat: Rainforest, secondary forest, and mixed wooded habitat on Madagascar.

Native range: Madagascar in scattered forest regions.

Wood-boring larvae, fruit, seeds, nectar, and fungi.

Aye-ayes are nocturnal, nesting in tree shelters by day and tapping, listening, and extracting food after dark.

They can live many years, giving the strange finger, learned routes, and night-foraging skill time to become mastery.

Females usually raise a single infant with long care in nests, letting young slowly learn the tapping and listening method.

Sexes are similar, so the elongated finger, large ears, and percussive foraging carry the main identity for both.

Rarity: Very rare · 87/100. Habitat loss and persecution have made aye-ayes rare and unevenly distributed.

• Keep distance and let the animal choose the space.
• Avoid blocking movement routes, nesting areas, or feeding behavior.
• Use optics, patience, and quiet observation instead of crowding for a closer view.