Monito Del Monte
The monito del monte (Spanish for "little bush monkey"), Dromiciops gliroides, also called chumaihuén in Mapudungun, is a diminutive marsupial native only to southwestern South America (Chile and Argentina).
The species is nocturnal and arboreal, and lives in thickets of South American mountain bamboo in the Valdivian temperate rain forests of the southern Andes, It has long been suspected that South American marsupials were ancestral to those of Australia, consistent with the fact that the two continents were connected via Antarctica in the early Cenozoic. Australia’s earliest known marsupial is Djarthia, a primitive mouse-like animal that lived about 55 million years ago. Djarthia had been identified as the earliest known australidelphian, and this research suggested that the monito del monte was the last of a clade which included Djarthia.
This implied that the ancestors of the Monito del Monte might have reached South America via a back-migration from Australia. The time of divergence between the Monito del Monte and Australian marsupials was estimated to have been 46 million years ago.
The monito del monte normally reproduces in the spring and can have a litter size varying anywhere from one to four young. The females have a pseudovagina, and a fur-lined pouch containing four mammae. When the young are mature enough to leave the pouch they are nursed in a nest, and then carried on the mother’s back. The young remain in association with the mother after weaning. Males and females both reach sexual maturity after 2 years. They are known to reproduce aggressively, sometimes leaving blood on the reproductive organs.