The golden-brown mouse lemur, also known as the Lac Ravelobe mouse lemur or the Ravelobe mouse lemur, is part of the family, Cheirogaleidae. These are the smallest species of lemur and are all arboreal, nocturnal, and typically social. All species of Lemur are native to the island of Madagascar. The golden-brown mouse lemur, Microcebus ravelobensis, was first discovered in 1994.
Geographic range and habitat
The island of Madagascar is located off the South-eastern coast of Africa. All species of lemur are indigenous to the island. The Golden-brown mouse lemur is isolated to the forest reserve of Ankarafantsika National Park, a dry deciduous forest located in northwestern Madagascar. It shares the habitat with the gray mouse lemur,, a sympatric species. Within the habitat that both the golden-brown lemur and gray mouse lemur live, they occupy two very different niches showing divergent regional distribution and different population density patterns. The golden-brown mouse lemur prefers habitat areas in lower latitudes that are humid and in close proximity to water resources. Whereas the gray mouse lemur populations increase with altitude and are located in drier habitats away from water sources. M. ravelobensis, as well as other species of mouse lemur have been classified as leaf or nest builders. The golden-brown mouse lemur’s habitat is well dispersed among sexes and family groups, showing little sign of intra- or interspecific competition among overlapping territories. In a 2009 study by S. Thoren et al. showed only lactating females were seen building nests, but studies suggest non-lactating females will also. Nest building will take place in the early hours of the night and will take approximately 60 minutes to build. The nests are constructed of small branches and leaves from surrounding vegetation. They will be occupied by lactating or dominant females, their offspring and mixed lineage group members for a period of 36 days.
Anatomy and physiology
The golden-brown mouse lemur has been categorized as a separate species based on morphology and genetics. Its dorsal side is golden-brown, and yellowish-white ventrally. It has a white stripe running from the lower forehead to the muzzle. It weighs 40-70g depending on the season, and is similar in appearance to the gray mouse lemur, though it has a longer, thinner tail. It is unable to store fat in its tail like other mouse lemurs. It travels through the forest by leaping, unlike the gray mouse lemur. It is a nocturnal species, and builds its nests in dense patches of vines or dead leaves.
Social distribution
There is a great variation in social patterns among nocturnal lemurs; the golden-brown mouse lemur is exceptional with its mixed-sex sleeping groups. M. ravelobensis has a well dispersed, inter-sexual sleeping pattern that promotes promiscuity was first categorized in 2004 by researchers Weidt, et al. The golden-brown mouse lemur sleeps predominantly in tree branches or makes nests. Because of this exposed environment male/female sleeping groups exist to aid in both thermoregulation of nests and decrease the chances of predation. This observation has also been noted by Radespiel et al.. Within the sleeping groups, there are several nest locations that individuals will switch between, but the members within the community never change. This social spatial distribution leads to overlapping territories that develop a multi-family community within a given range. Within this given range, studies show little or no competition between males during mating season. Though golden-brown mouse lemurs exhibit a social sleeping pattern, their active nocturnal lifestyle is typically solitary.
