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Lorises

Lorises, Slow And Not So Slow, Galagos Or Bushbabies

The loris or bushbaby family, Lorisidae, includes 14 species of Asian and African primates. Loris is a Dutch word for clown, given to these amusing creatures by European seaman who saw them. With the lemurs, these attractive little primates make up the group called prosimians, or "pre-monkeys." All lemurs are found on the big island of Madagascar; other members of the loris family can be found elsewhere. Unlike the lemurs, the lorisids have little or no tail.

The family is divided into two subfamilies—the Lorisinae, including the slow-moving pottos and lorises, and the Galaginae, the quick-moving galagos. The galagos, or bushbabies, are limited to Africa, but the lorises and the pottos have expanded into India and southeast Asia.

All of these tree-living primates are nocturnal, active in nighttime. This fact keeps them from competing with the monkeys with which they share their habitat. Therefore, the monkeys are asleep when the lorisids are active. Like other prosimians, they have a reflective layer, called the tapetum lucidum, in back of the retina of the eye. This allows them to see when there is very little light. It also makes their eyes shine in the dark, like a cat's eye.

Like the lemurs, but not like the related tarsiers, lorisids have rhinariums, which are rough-skinned, moist noses indicating that scent is very important in their lives. They mark their paths for other lorises as they move throughout their range by wetting their hands and feet in urine. They apparently prefer to stay alone in their territories except during breeding season.

Lorisids have front bottom teeth that point forward, forming a dental comb used in grooming and feeding. Underneath the tongue is a hard structure with points that are used to clean the dental comb. Lorisids can also groom their soft fur with the toilet claw. This is a special claw located on the second toe. All other fingers and toes bear flat nails. This does not mean that they have trouble climbing, however. Their feet bear a single opposable big, or first, toe that allows them to grasp branches tightly. This grasping ability allows the lorisids to hang securely upside down, dangling from their hind feet while they eat with their hands, or perhaps just for play. The lorisids' diet includes fruit, insects, and the oozing gum of trees.

Lorisids range in size from the tiny dwarf bushbaby (Galago demidovii) at 2.1 oz (60 g) to the plump potto (Perodicticus potto), which may reach more than 2 lb (1 kg). Though it is not known how long these primates live in the wild, they have been known to reach 12, even 14 years in captivity.


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