|
The mouse lemurs are nocturnal lemurs of the genus ''Microcebus''. Like all lemurs, mouse lemurs are native to Madagascar. Mouse lemurs have a combined head, body and tail length of less than , making them the smallest primates〔(【引用サイトリンク】title=Primate Factsheets: Mouse lemur (Microcebus) Taxonomy, Morphology, & Ecology )〕 (the smallest species being Madame Berthe's mouse lemur); however, their weight fluctuates in response to daylight duration.〔Andrès M, Gachot-Neveu H, Perret M. 2001. Genetic determination of paternity in captive grey mouse lemurs: pre-copulatory sexual competition rather than sperm competition in a nocturnal prosimian? Behaviour 138(8):1047-63.〕 Lemurs and Mouse Lemurs were announced by the IUCN as the most endangered of all vertebrates. There are about 21 mouse lemur species identified by 2015. There were only 2 known mouse lemur species by 1992.〔(【引用サイトリンク】title=Yoder Lab - Research )〕 It was estimated that the 21 mouse lemur species evolved from a common ancestor 10 million years ago. Evolution of mouse lemurs is an example for adaptive radiation. Mouse lemurs are omnivorous; their diets are diverse and include insect secretions, arthropods, small vertebrates, gum, fruit, flowers, nectar, and also leaves and buds depending on the season. Mouse lemurs are considered cryptic species - with very little morphological differences between the various species, but with high genetic diversity. Recent evidence points to differences in their mating calls, which is very diverse. Since the mouse lemurs are nocturnal, they might not have evolved to look differently, but had evolved various auditory and vocal systems. Mouse lemurs have the smallest known brain of any primate, at just 0.004 pounds (2 grams).〔http://news.softpedia.com/news/Top-10-Brains-83944.shtml〕 ==Reproduction and Evolution== Mouse lemurs are also known for their sperm competition. During breeding seasons, the testicles of male mouse lemurs increases in size about 30% of their normal size. This was speculated to increase the sperm production thereby conferring an advantage for the individual to bear more offspring. There are various hypotheses relating the rapid evolution of mouse lemur species this sperm competition.〔Folia Primatol (Basel). 2003 Sep-Dec;74(5-6):355-66. Mating system in mouse lemurs: theories and facts, using analysis of paternity. Andrès M1, Solignac M, Perret M.〕 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「Mouse lemur」の詳細全文を読む スポンサード リンク
|