Ringtail at Sunset © photo by Paul Boucher

Lemurs are a separate branch of the Primates, the order of monkeys, apes, and people. With the lorises, pottos and bushbabies of Africa and Asia, they are prosimians, that is, "pre-monkeys", although the first monkey and ape lineages may have evolved almost as early as the prosimians. Lemur-like fossils are found in Wyoming and in the Paris Basin, dating to about 50 M years ago, although molecular evidence suggests they originated much earlier, perhaps in the southern hemisphere. True lemurs now exist only in Madagascar which the monkeys and apes never reached. There, they have diverged into a remarkable variety of body plans, classed as five separate families. Each forest of the island has its own suite of forms, totalling about seventy named kinds, although there is dispute which are true species and which are subspecies..

Madagascar is a place where whole new species are still being found, like Propithecus tattersalli, the golden-crowned sifaka. Many which were previously grouped together are now clearly different forms, like the suite of western mouselemurs.

Berenty itself has six species: white sifakas, ringtailed lemurs, introduced brown lemurs, and three nocturnal forms: white-footed lepilemurs, grey mouselemurs, and the newly recognized red-and-grey mouselemurs.