Lorisidae – Lorisids

Famously motionless, yet recent studies proved not all family members are slow-moving

This family includes lorises, pottos, and angwantibos, found across southern Asia and the tropical regions of central Africa. These primates are characterized by their slow, deliberate movements, nocturnal habits, and remarkable adaptability to life in the trees.

Lorisids are primarily arboreal, spending most of their lives in the canopy, where they have evolved several physical and behavioral adaptations to navigate and survive in this environment. One of the most notable adaptations is their hands and feet, equipped with an extremely strong grip. This gripping ability is enhanced by a network of fine capillaries beneath their skin, known as “miracle nets,” which prevents their extremities from going numb even after hours of hanging motionless from branches. This adaptation allows them to conserve energy and remain immobile for extended periods, making them less noticeable to predators and prey alike.

Their diet is predominantly insectivorous, relying on a variety of insects for nutrition. However, their dietary habits are versatile, including bird eggs, small vertebrates, berries, and sap. This diversity in their diet reflects their ability to exploit a range of food sources available in their forested habitats.

Territorial behavior is common among members of the Lorisidae family, with territory marking through urine being a prevalent practice. This communicates occupancy and aids in social interactions and mating behaviors. Additionally, urine washing, where individuals bathe their hands and feet in urine, is routine. While the exact purpose of this behavior is not fully understood, it is believed to play roles in scent marking, self-cleaning, and possibly even in thermoregulation or parasite control.

Some lorisid species possess brachial glands on their upper arms, which secrete a substance that can become toxic when mixed with saliva. This unique chemical defense mechanism is primarily used as a deterrent against predators but can also be used in intraspecific conflicts.