The Aye-aye (Daubentonia madagascariensis) is a lemur, a strepsirrhine primate which is a native to Madagascar. It blends the long teeth feature of a rodent along with a slender third finger. This brings the Aye-Aye and the woodpecker into the same ecological niche. The largest nocturnal primate has a bizarre way of finding food. It taps on trees to find grubs, then nibbles holes into the wood, inserts its slender and elongated third finger to pull out the grubs. The rare Aye-Aye does not resemble its primates at instance, but they are related to the Apes, chimpanzees, and even the humans.

The Aye-aye lemurs are black or dark brown in color and have a distinguishing bushy tail which is larger than their miniscule body. They are also characterized by their big eyes, long and narrow fingers, and their large and sensitive ears. The Aye-Aye lemur has a pointed claw on all their fingers and toes except for their exceptional big toes, which allows them to hang from branches of trees. The face is paler compared to the rest of the body characterized with large, leathery ears and the prominent, yellowish-orange eyes. They weigh around 3kgs (6.6lbs) and grows in length from 30–37 centimeters (12–15 in) from head to body and a 44–53 centimeter (17–21 in) tail. Other than the sex organs and the weight, the aye-aye lemurs do not show any sort of sexual dimorphism.

The Aye-Aye lemur mostly lives on the eastern Madagascar coast. They spend most of their life in the deciduous or the rain forest trees and stay away from the earth. These nocturnal creatures almost spend the day curled up in a ball-like nest made of branches and leaves. The nest is closed circular structure with a single entry hole, present in the forks of large big trees.

The Aye-Aye lemurs are polygamous. They compete with other males for mates. The male Lemurs are extremely aggressive, and even pull other males away from the female during mating. Other than mating the males and the females interact only during hunting. The males usually stay close to the pregnant female, till the infant is born and grows up a little. The Aye-Aye lemur mostly eats nuts, grubs, fruits, nectar, seeds, and even fungi, categorizing it as an Omnivore. The Aye-Ayes tap on the branches and trunks of the trees at about 8 times per second and listens to the echo produced. Once they find a chamber gnaw a hole into the wood and get the grubs out of that hole with their slender third finger.

The Aye-Aye lemur is considered as an omen by many natives of Madagascar. As a result they are often killed at sight. Along with the habitat destruction and such type of barbaric hunting have made the Aye-Aye lemur critically endangered nearly threatened species.