All About Lemurs

 Lemur, (suborder Strepsirrhini), any primitive primate other than the tarsier; more precisely, any of Madagascar's indigenous primates. In a broad sense, the term lemur refers not only to the typical lemurs (family Lemuridae), but also to Madagascar's avahis, sifakas, indri, and aye-aye, as well as Southeast Asia's and the Philippines' colugos, as well as Southeast Asia's and Africa's lorises, potto, and bush babies. Strictly speaking, it excludes the last three (the Lorisiformes).

The majority of Madagascar's lemurs and the neighbouring Comoro Islands have large eyes, fox-like faces, monkey-like bodies, and long hind limbs. The length of a lemur (excluding the tail) varies from approximately 9 cm (3.5 inches) for Madame Berthe's mouse lemur (Microcebus berthae) to nearly 70 cm (28 inches) for the indri (Indri indri). Lemurs' bushy tails can grow to be as long as their bodies; the indri, on the other hand, has only a stub of a tail. Except for the aye-aye, lemurs have woolly fur that ranges in colour from reddish to grey to brown to black; some species have varying degrees of white patterning. They may also have eye-rings or crown patches, in addition to other markings.

Lemurs have a lower intelligence level than monkeys. Their sense of smell is enhanced, but their vision is impaired. While some species are active during the day, their eyes appear to have been adapted for nocturnal life, sacrificing acuity in favour of increased sensitivity in low light conditions. All lemurs have a reflective layer (tapetum) behind the retina of the eye, but no fovea or macula lutea; a hairless, moist tip to the muzzle; a noninvasive (epitheliochorial) placenta; comblike forward-directed lower front teeth (except for the aye-aye); and a claw (“toilet claw”) on the second toe of the foot.

Lemurs are gregarious, docile animals; some species live in groups of ten or more. They spend the majority of their time in trees eating fruit, leaves, buds, insects, small birds, and birds' eggs, but diets vary among species. Certain species, for example, are primarily insectivorous, while others subsist almost entirely on foliage. Every species breeds seasonally, and females may have only one fertile day per year. After two to five months of gestation, single offspring are typically born. The newborn lemur then clings to the underside of its mother until it is mature enough to ride on her back.

Numerous lemurs are endangered or rare. Numerous species were either discovered in the late twentieth century or were rediscovered after being thought extinct. There are remains of species larger than any of the modern lemurs. Some of these may have lasted only 500 years. They were probably exterminated by the Malagasy people, who arrived on the island less than 2,000 years ago, through overhunting or habitat modification.

Diversification of lemurs

The "true lemurs" (family Lemuridae) are comprised of five genera and approximately twenty species. The most well-known is the ring-tailed lemur (Lemur catta), which is frequently seen in zoos. It is unique both in its habitat (parts of Madagascar that are dry and rocky) and in its striped tail (all other lemurs have solid-coloured tails). Troops are composed of a mix of males and females, with females serving as the dominant sex. A male denotes the troop's territory by slashing the trunk of a small tree with a horny spur on his wrist, eliciting an audible click, and leaving a fragrant scar on the tree. The related genus Eulemur includes the black lemur (E. macaco), which has a black male and a reddish brown female. The rare black-and-white or black-and-red ruffed lemurs (genus Varecia) inhabit Madagascar's eastern rainforests. In the island's eastern and northwestern rainforests, the gentle lemurs, or lesser bamboo lemurs (genus Hapalemur), and the critically endangered greater bamboo lemurs (Prolemur simus), feed on bamboo stems.

At least 25 sportive lemur species (family Lepilemuridae) inhabit Madagascar's rainforests and dry forests. They are nocturnal and solitary, feeding on leaves and flowers that are digested by bacteria in their enormous cecum. Bacterial fermentation enables energy to be extracted from the lemur's diet's large amount of otherwise indigestible cellulose.

Dwarf lemurs (Cheirogaleus), along with mouse (Microcebus), Coquerel's (Mirza), hairy-eared (Allocebus), and fork-crowned (Phaner) lemurs, comprise the family Cheirogaleidae, which is in many ways the most primitive living lemur family. Dwarf lemurs store fat in their tails and hibernate (estivate) during dry seasons; they are monogamous. The smallest living primates are mouse lemurs, which eat insects and fruit. Fork-crowned lemurs are forest dwellers along Madagascar's western coast, subsisting on gum and insects.

Strepsirrhine primates first appeared in the Early Eocene Epoch (approximately 50 million years ago), though their origins date all the way back to the Paleocene Epoch. These Eocene lemuroids were common in North America and Europe, and several have been identified through the study of complete skeletons. By the Eocene's end (approximately 34 million years ago), strepsirrhines had virtually vanished from the Northern Hemisphere. However, the lemur lineage persisted in tropical forests, and they were especially successful in Madagascar, where some members of the lineage may have floated across the Mozambique Channel on vegetation mats some 50 million years ago. Lemurs were relatively unaffected by competition from more advanced primates on Madagascar. Fossils from Egypt and Kenya dating to 34 million years ago indicate that the ancestors of modern aye-ayes (Daubentonia madagascariensis) originated in Africa before dispersing to Madagascar, implying that at least two distinct lemur migrations occurred to the island.