Monito del Monte
Overview
The Monito del Monte
The Monito del Monte (Spanish
Spanish language
Spanish , also known as Castilian , is a Romance language in the Ibero-Romance group that evolved from several languages and dialects in central-northern Iberia around the 9th century and gradually spread with the expansion of the Kingdom of Castile into central and southern Iberia during the...

 for "little mountain monkey", Dromiciops gliroides, is a diminutive marsupial native only to southwestern South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 (Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

 and Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

). It is the only extant species in the ancient order Microbiotheria
Microbiotheria
The Monito del Monte is the only extant member of its family and the only surviving member of an ancient order, the Microbiotheria. The oldest microbiothere currently recognised is Khasia cordillerensis, based on fossil teeth from Early Palaeocene deposits at Tiupampa, Bolivia...

, and the sole New World representative of the superorder Australidelphia
Australidelphia
Australidelphia is the superorder that contains roughly three-quarters of all marsupials, including all those native to Australasia and a single species from South America...

 (all other New World marsupials are members of Ameridelphia
Ameridelphia
Ameridelphia is traditionally a superorder that includes all marsupials living in the Americas except for the Monito del Monte...

). It is sometimes called the colocolo, but not often because there is also a wild cat
Colocolo
Colocolo may refer to:*Colocolo , a Mapuche tribal chief.*Colo Colo creature of the Mapuche mythology.*Colocolo , a South American cat native to Chile.*Colo-Colo, a Chilean football team....

 which shares the name.
Encyclopedia
The Monito del Monte
The Monito del Monte (Spanish
Spanish language
Spanish , also known as Castilian , is a Romance language in the Ibero-Romance group that evolved from several languages and dialects in central-northern Iberia around the 9th century and gradually spread with the expansion of the Kingdom of Castile into central and southern Iberia during the...

 for "little mountain monkey", Dromiciops gliroides, is a diminutive marsupial native only to southwestern South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...

 (Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

 and Argentina
Argentina
Argentina , officially the Argentine Republic , is the second largest country in South America by land area, after Brazil. It is constituted as a federation of 23 provinces and an autonomous city, Buenos Aires...

). It is the only extant species in the ancient order Microbiotheria
Microbiotheria
The Monito del Monte is the only extant member of its family and the only surviving member of an ancient order, the Microbiotheria. The oldest microbiothere currently recognised is Khasia cordillerensis, based on fossil teeth from Early Palaeocene deposits at Tiupampa, Bolivia...

, and the sole New World representative of the superorder Australidelphia
Australidelphia
Australidelphia is the superorder that contains roughly three-quarters of all marsupials, including all those native to Australasia and a single species from South America...

 (all other New World marsupials are members of Ameridelphia
Ameridelphia
Ameridelphia is traditionally a superorder that includes all marsupials living in the Americas except for the Monito del Monte...

). It is sometimes called the colocolo, but not often because there is also a wild cat
Colocolo
Colocolo may refer to:*Colocolo , a Mapuche tribal chief.*Colo Colo creature of the Mapuche mythology.*Colocolo , a South American cat native to Chile.*Colo-Colo, a Chilean football team....

 which shares the name. The species is nocturnal and arboreal, and lives in thickets of Chilean bamboo
Chusquea
Chusquea is a genus of bamboo with about 150 species. Most of them are mountain clumping bamboos native from southern Mexico to southern Chile and Argentina. They are sometimes referred to as South American mountain bamboos. Unlike most other bamboos, the stems of these species are solid, not hollow...

 in the Valdivian temperate rain forests
Valdivian temperate rain forests
The Valdivian temperate rain forests are a temperate broadleaf and mixed-forest ecoregion located on the west coast of southern South America, lying mostly in Chile and extending into a small part of Argentina. It is part of the Neotropic ecozone. The forests are named after the city of Valdivia...

 of the southern Andes
Andes
The Andes is the world's longest continental mountain range. It is a continual range of highlands along the western coast of South America. This range is about long, about to wide , and of an average height of about .Along its length, the Andes is split into several ranges, which are separated...

, aided by its partially prehensile tail
Prehensile tail
A prehensile tail is the tail of an animal that has adapted to be able to grasp and/or hold objects. Fully prehensile tails can be used to hold and manipulate objects, and in particular to aid arboreal creatures in finding and eating food in the trees...

. It eats primarily insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

s and other small invertebrates, supplemented with fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...

.

Phylogeny and biogeography

It has long been suspected that South American marsupials were ancestral to those of Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

, consistent with the fact that the two continents were connected via Antarctica in the early Cenozoic
Cenozoic
The Cenozoic era is the current and most recent of the three Phanerozoic geological eras and covers the period from 65.5 mya to the present. The era began in the wake of the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and...

. Australia’s earliest known marsupial is Djarthia
Djarthia
Djarthia is an extinct genus of marsupial. It is the oldest marsupial found in Australia, discovered at the Murgon fossil site in south-eastern Queensland. Skeletal materal described include molar, incomplete cochlear and tarsal bone either complete or in fragmented state of preservation....

, a primitive mouse
Mouse
A mouse is a small mammal belonging to the order of rodents. The best known mouse species is the common house mouse . It is also a popular pet. In some places, certain kinds of field mice are also common. This rodent is eaten by large birds such as hawks and eagles...

-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
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 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. However, in 2010, analysis of retrotransposon
Retrotransposon
Retrotransposons are genetic elements that can amplify themselves in a genome and are ubiquitous components of the DNA of many eukaryotic organisms. They are a subclass of transposon. They are particularly abundant in plants, where they are often a principal component of nuclear DNA...

 insertion sites in the nuclear DNA
Nuclear DNA
Nuclear DNA, nuclear deoxyribonucleic acid , is DNA contained within a nucleus of eukaryotic organisms. In mammals and vertebrates, nuclear DNA encodes more of the genome than the mitochondrial DNA and is composed of information inherited from two parents, one male, and one female, rather than...

 of a variety of marsupials, while confirming the placement of the Monito del Monte in Australidelphia, showed that its lineage
Lineage (evolution)
An evolutionary lineage is a sequence of species, that form a line of descent, each new species the direct result of speciation from an immediate ancestral species. Lineages are subsets of the evolutionary tree of life. Lineages are often determined by the techniques of molecular systematics.-...

 is the most basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...

 of that superorder. The study also confirmed that the most basal of all marsupial orders are the other two South American lineages (Didelphimorphia
Didelphimorphia
Opossums make up the largest order of marsupials in the Western Hemisphere, including 103 or more species in 19 genera. They are also commonly called possums, though that term technically refers to Australian fauna of the suborder Phalangeriformes. The Virginia opossum was the first animal to be...

 and Paucituberculata, with the former probably branching first). This indicates that Australidelphia arose in South America (along with the ancestors of all other living marsupials), and probably reached Australia in a single dispersal event
Biological dispersal
Biological dispersal refers to species movement away from an existing population or away from the parent organism. Through simply moving from one habitat patch to another, the dispersal of an individual has consequences not only for individual fitness, but also for population dynamics, population...

 after Microbiotheria
Microbiotheria
The Monito del Monte is the only extant member of its family and the only surviving member of an ancient order, the Microbiotheria. The oldest microbiothere currently recognised is Khasia cordillerensis, based on fossil teeth from Early Palaeocene deposits at Tiupampa, Bolivia...

 split off.

Reproduction

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
Nest
A nest is a place of refuge to hold an animal's eggs or provide a place to live or raise offspring. They are usually made of some organic material such as twigs, grass, and leaves; or may simply be a depression in the ground, or a hole in a tree, rock or building...

, 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.

Habitat

Monitos del Monte mainly live in trees, where they construct spherical nests of water resistant bamboo leaves. These leaves are then lined with moss or grass, and placed in well protected areas of the tree. The nests are sometimes covered with grey moss as a form of camouflage
Camouflage
Camouflage is a method of concealment that allows an otherwise visible animal, military vehicle, or other object to remain unnoticed, by blending with its environment. Examples include a leopard's spotted coat, the battledress of a modern soldier and a leaf-mimic butterfly...

. These nests provide the Monito del Monte with some protection from the cold, both when it is active and when it hibernates
Hibernation
Hibernation is a state of inactivity and metabolic depression in animals, characterized by lower body temperature, slower breathing, and lower metabolic rate. Hibernating animals conserve food, especially during winter when food supplies are limited, tapping energy reserves, body fat, at a slow rate...

. It stores fat in the base of its tail for winter hibernation
Hibernation
Hibernation is a state of inactivity and metabolic depression in animals, characterized by lower body temperature, slower breathing, and lower metabolic rate. Hibernating animals conserve food, especially during winter when food supplies are limited, tapping energy reserves, body fat, at a slow rate...

. It lives in the dense, humid forests of highland Chile and Argentina.

Role as a seed disperser

A study performed in the temperate forests of southern Argentina showed a mutualistic seed dispersal relationship between D. gliroides and Tristerix
Tristerix
Tristerix is a genus of mistletoe in the family Loranthaceae, native to the Andes from Colombia to Chile. They are a woody perennial usually occurring as an aerial parasite, often pollinated by hummingbirds...

 corymbosus
, also known as the Loranthacous mistletoe
Mistletoe
Mistletoe is the common name for obligate hemi-parasitic plants in several families in the order Santalales. The plants in question grow attached to and within the branches of a tree or shrub.-Mistletoe in the genus Viscum:...

. The Monito del Monte is the single dispersal agent for this plant, and without it the plant would go extinct. The Monito del Monte eats the fruit of T. corymbosus, and thus disperses the seeds. Scientists speculate that the coevolution of these two species could have begun 60-70 million years ago.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
x
OK