The fat-tailed dwarf lemur (''Cheirogaleus medius''), also known as the lesser dwarf lemur, western fat-tailed dwarf lemur, or spiny forest dwarf lemur, is endemic to

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

Hibernation

Recent research has shown that ''C. medius'' hibernates (or aestivates), even though in the tropical winter of Madagascar, temperatures remain high. It is the first tropical mammal and only primate in which hibernation has been demonstrated. However, the Malagasy winter is dry, and it appears that the

lemur Lemurs ( ) (from Latin ''lemures'' – ghosts or spirits) are Strepsirrhini, wet-nosed primates of the Superfamily (biology), superfamily Lemuroidea (), divided into 8 Family (biology), families and consisting of 15 genera and around 100 exist ...

is avoiding the drought. It can hibernate for seven months. Unlike animals that hibernate in temperate regions, the lemur does not control its body temperature while hibernating, and if the tree hole in which it is sleeping is not well insulated, its body temperature fluctuates in accordance with the outside temperature. During torpor, this lemur has been found to periodically enter

REM sleep Rapid eye movement sleep (REM sleep or REMS) is a unique phase of sleep in mammals and birds, characterized by random rapid movement of the eyes, accompanied by low muscle tone throughout the body, and the propensity of the sleeper to dream viv ...

;

non-REM sleep Non-rapid eye movement sleep (NREM), also known as quiescent sleep, is, collectively, sleep stages 1–3, previously known as stages 1–4. Rapid eye movement sleep (REM) is not included. There are distinct electroencephalographic and other char ...

has not been observed, a pattern opposite that found in hibernating

ground squirrel Ground squirrels are members of the squirrel family of rodents ( Sciuridae), which generally live on or in the ground, rather than trees. The term is most often used for the medium-sized ground squirrels, as the larger ones are more commonly known ...

s. The REM sleep episodes occurred during periods of higher ambient temperature (averaging 27 C, versus an average of 20 C during nonsleeping intervals while in torpor). ''C. medius'' has a significantly longer lifespan than other strepsirrhinine or nonstrepsirrhinine primates of similar size, and this longevity is thought to be related to its status as the only primate that is an obligatory hibernator. Its maximum lifespan in captivity is nearly 30 years. Like other fat-tailed lemurs, ''C. medius'' is able to store

fat In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food. The term often refers spec ...

in its tail, and this provides a source of energy during its period of dormancy.

Reproduction

Although most ''C. medius'' live in areas where the environment is dry, there are those who live in tropical rain forest. Through research, it is understood that these animals hibernation period is linked to their reproduction strategies. In the rainforest these lemurs are in more in an active state than they would be in a dry forest. This level of high activity from the lemurs is linked to higher reproduction rates according to Dr. Lahann.

Taxonomy

Between 2000 and 2009, a population of dwarf lemur was known as a separate species, the southern fat-tailed dwarf lemur (''Cheirogaleus adipicaudatus''). It was described by taxonomist

Colin Groves Colin Peter Groves (24 June 1942 – 30 November 2017) was a British-Australian biologist and anthropologist. Groves was Professor of Biological Anthropology at the Australian National University in Canberra, Australia. Education Born in Englan ...

as having a

pelage Fur is a thick growth of hair that covers the skin of mammals. It consists of a combination of oily #Guard hair, guard hair on top and thick #Down hair, underfur beneath. The guard hair keeps moisture from reaching the skin; the underfur acts as ...

coloration that is dark

dorsally Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

and gray

ventral Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. Th ...

ly, with a vaguely expressed dorsal stripe running down the back, a relatively short white median facial stripe, and black eye-rings. However, in 2009, Groeneveld ''et al.'' demonstrated genetically that ''Cheirogaleus adipicaudatus'' was a synonym of ''Cheirogaleus medius'', so the southern fat-tailed dwarf lemur is no longer recognized as a species.

Traits

This species is nocturnal, with a diet of insects, other small animals, fruits and flowers. The adult lemur mass is 160 grams.

Hibernation

Reproduction

Taxonomy

Traits

References

Further reading