Lemurs are part of a class of primates known as prosimians. These animals are the evolutionary predecessors of monkeys (simians). The term "lemur" is generically used for several families of prosimians: Cheirogaleidae, Megaladapidae, Lemuridae, Indridae, and Daubentoniidae. It is derived from the Latin word lemures, which means "spirits of the night." This likely refers to many lemurs' nocturnal behavior and their large, reflective eyes.
In taxonomy, the genus Lemur has only one member: Lemur catta, or the ring-tailed lemur. It is easily recognized by its black and white striped tail, and is found in many zoos.
Lemurs are found naturally only on the island of Madagascar, and some smaller surrounding islands, including the Comoros. They made their way across the ocean after the island broke away from the continent of Africa. While they were displaced in the rest of the world by monkeys, apes, and other primates, the lemurs were safe from competition on Madagascar and differentiated into a number of species. These ranged in size from about 30 grams to perhaps as large as 200 kilograms. The larger species have all become extinct since humans settled on Madagascar, and since the early 20th century the largest lemurs reach about 7 kilograms. Typically, the smaller lemurs are active at night (nocturnal), while the larger ones are active during the day (diurnal).
All lemurs are endangered species, due mainly to habitat destruction (deforestation) and hunting. Although conservation efforts are under way, options are limited because of the lemurs' limited range and because Madagascar is desperately poor. Currently, there are approximately 32 living lemur species.
One of the foremost lemur research facilities is the Duke University Primate Center. " class="external">http://www.duke.edu/web/primate/