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The giant mouse lemurs (''Mirza'') are a genus of strepsirrhine primates. Two species have been formally described; the northern giant mouse lemur (''Mirza zaza'') and Coquerel's giant mouse lemur (''Mirza coquereli''). Like all other lemurs, they are native to Madagascar, where they are found in the western dry deciduous forests and further to the north in the Sambirano valley and Sahamalaza Peninsula. First described in 1867 as a single species, they were grouped with mouse lemurs and dwarf lemurs. In 1870, British zoologist John Edward Gray assigned them to their own genus, ''Mirza''. The classification was not widely accepted until the 1990s, which followed the revival of the genus by American paleoanthropologist Ian Tattersall in 1982. In 2005, the northern population was declared a new species, and in 2010, the World Wide Fund for Nature announced that a southwestern population might also be a new species. Giant mouse lemurs are about three times larger than mouse lemurs, weighing approximately , and have a long, bushy tail. They are most closely related to mouse lemurs within Cheirogaleidae, a family of small, nocturnal lemurs. Giant mouse lemurs sleep in nests during the day and forage alone at night for fruit, tree gum, insects, and small vertebrates. Unlike many other cheirogaleids, they do not enter a state of torpor during the dry season. The northern species is generally more social than the southern species, particularly when nesting, though males and females may form pair bonds. The northern species also has the largest testicle size relative to its body size among all primates and is atypical among lemurs for breeding year-round instead of seasonally. Home ranges often overlap, with related females living closely together while males disperse. Giant mouse lemurs are vocal, although they also scent mark using saliva, urine, and secretions from the anogenital scent gland. Predators of giant mouse lemurs include the Madagascar buzzard, Madagascar owl, fossa, and the narrow-striped mongoose. Giant mouse lemurs reproduce once a year, with two offspring born after a 90-day gestation. Babies are initially left in the nest while the mother forages, but are later carried by mouth and parked in vegetation while she forages nearby. In captivity, giant mouse lemurs will breed year-round. Their lifespan in the wild is thought to be five to six years. Both species are listed as endangered due to habitat destruction and hunting. Like all lemurs, they are protected under CITES Appendix I, which prohibits commercial trade. Despite breeding easily, they are rarely kept in captivity. The Duke Lemur Center coordinated the captive breeding of an imported collection of the northern species, which rose from six individuals in 1982 to 62 individuals by 1989, but the population fell to six by 2009 and was no longer considered a breeding population. ==Taxonomy== The first species of giant mouse lemur was described by the French naturalist Alfred Grandidier in 1867 based on seven individuals he had collected near Morondava in southwestern Madagascar. Of these seven specimens, the lectotype was selected in 1939 as MNHN 1867–603, an adult skull and skin. Naming the species after the French entomologist Charles Coquerel, Grandidier placed Coquerel's giant mouse lemur (''M. coquereli'') with the dwarf lemurs in the genus ''Cheirogaleus'' (which he spelled ''Cheirogalus'') as ''C. coquereli''. He selected this generic assignment based on similarities with fork-marked lemurs (''Phaner''), which he considered to also be members of ''Cheirogaleus''. The following year, the German naturalist Hermann Schlegel and Dutch naturalist François Pollen independently described the same species and coincidentally gave it the same specific name, ''coquereli'', basing theirs on an individual from around the Bay of Ampasindava in northern Madagascar. Unlike Grandidier, they placed their specimen in the genus ''Microcebus'' (mouse lemurs); however, these authors also listed all ''Cheirogaleus'' under ''Microcebus'' and based the classification of their species on similarities with the greater dwarf lemur (''M. typicus'', now ''C. major''). In 1870, the British zoologist John Edward Gray placed Coquerel's giant mouse lemur into its own genus, ''Mirza''. This classification was widely ignored and later rejected in the early 1930s by zoologists Ernst Schwarz, Guillaume Grandidier, and others, who felt that its longer fur and bushy tail did not merit a separate genus and instead placed it in ''Microcebus''. British anatomist William Charles Osman Hill also favored this view in 1953, noting that despite its larger size (comparable to ''Cheirogaleus''), its first upper premolar was proportionally small as in ''Microcebus''. In 1977, French zoologist Jean-Jacques Petter also favored the ''Microcebus'' classification, despite the threefold size difference between Coquerel's giant mouse lemur and the other members of the genus. The genus ''Mirza'' was resurrected in 1982 by American paleoanthropologist Ian Tattersall to represent an intermediate branch between ''Microcebus'' and ''Cheirogaleus'', citing the Coquerel's giant mouse lemur's significantly larger size than the largest ''Microcebus'' and locomotor behavior more closely aligned with ''Cheirogaleus''. Adoption of ''Mirza'' was slow, though in 1994 it was used in the first edition of ''Lemurs of Madagascar'' by Conservation International. In 1993, primatologist Colin Groves initially favored the ''Microcebus'' classification in the second edition of ''Mammal Species of the World'', but began supporting the resurrection of ''Mirza'' in 2001. In 1991, prior to adopting ''Mirza'', Groves was the first to use the common name "giant mouse lemur". Prior to that, they were popularly referred to as "Coquerel's mouse lemur". In 2005, Peter M. Kappeler and Christian Roos described a new species of giant mouse lemur, the northern giant mouse lemur (''M. zaza''). Their studies compared the morphology, behavioral ecology, and mitochondrial cytochrome b sequences of specimens from both Kirindy Forest in central-western Madagascar and around Ambato in northwestern Madagascar, part of the Sambirano valley. Their study demonstrated distinct differences in size, sociality, and breeding, as well as sufficient genetic distance to merit specific distinction between the northern and central-western populations. Because Grandidier's description was based on a southern specimen, they named the northern population as a new species. The World Wide Fund for Nature (WWF) announced in 2010 that a biodiversity study from 2009 in the gallery forest of Ranobe near Toliara in southwestern Madagascar revealed a population of giant mouse lemurs previously unknown to science, and possibly a new species. They noted a significant difference in coloration between the two known species and the specimen they observed. However, further testing was required to confirm the discovery. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「giant mouse lemur」の詳細全文を読む スポンサード リンク
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