Metachirus nudicaudatus, brown four eyed opossums, range from Nicaragua to Paraguay and N. Argentina (Redford and Eisenburg, 1992).
Brown four eyed opossums are both arboreal and terrestrial, but more often are found on the ground. They inhabit lowlands, heavy forests, or open brush country. They build round nests in tree branches or at times under rocks and logs (Hunsaker, 1977). The nests are made of leaves and twigs (Nowak, 1997).
In general, M. nudicaudatus is grayish-brown in color. The back and sides are darker brown. The head has a dark band stretching from the tip of the snout over the eyes and across the base of the ear, making the face look almost black. In some individuals, this band extends past the ears. The eyes are large, rounded, and completely dark. A creamy white spot over each eye gives the animals their "four-eyed" name. The fur is short, thick, and silky. The venter (belly or abdomen) is usually white or cream. The tail is furred partially near the base. The rest of the tail, the scaly part, is multicolored--part black and part white. The length of the tail is usually around 330 mm, being longer than the body which is about 265 mm (Nowak, 1997; Redford and Eisenburg, 1992). The females are 71% lighter than the males (Hansen et al., 1999).
Brown four eyed opossums are seasonally polyestrous, meaning that they are capable of breeding many times through out the year. In Central America, though, they are reported to breed in November. The female of this species does not have a pouch like most marsupials. Instead lateral folds of skin exist on the lower abdomen, on which the mammae are located (females with 5, 7, and 9 have all been recorded). Therefore, the young does not crawl into the pouch after birth like other marsupials. A 51-mm young was reported to be capable of standing on its own. It rode on its mother's hips or back and was fully independent 2 months later (Nowak, 1997).
The maximum lifespan of M. nadicaudatus is three to four years (Nowak, 1997)
Brown four eyed opossums are completely nocturnal, hardly moving from their nests until dark. In a capture-mark-recapture study over two years, M. nudicaudatus was found to be highly mobile and exploratory. It also had a short residence time. It has been observed that when M. nudicaudatus is held in the hand it hardly makes any noise (Nowak, 1997; Gentile and Cerquiera, 1995).
This species is mainly frugivorous. However, their diet can also include insects, bird's eggs, small vertebrates such as reptiles, and also small invertebrates (Hunsaker, 1977). In a study which examined the feces of individuals, some brown four eyed opossums were found to consume more ants, termites, cockroaches and beetles than any other food in their diet (Freitas et al., 1997).
As an insectivore, M. nudicaudatus clearly helps to keep the numbers of insects in its habitat under control (Freitas et al., 1997).
Brown four eyed opossums consume pests such as ants, termites, and cockroaches (Frietas et al., 1997).
This species has been accused of destroying fruit crops in certain areas (Nowak, 1997).
LeeAnn Bies (author), University of Michigan-Ann Arbor, Kate Teeter (editor), University of Michigan-Ann Arbor.
living in the southern part of the New World. In other words, Central and South America.
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
uses smells or other chemicals to communicate
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
parental care is carried out by females
union of egg and spermatozoan
forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.
an animal that mainly eats fruit
An animal that eats mainly plants or parts of plants.
fertilization takes place within the female's body
having the capacity to move from one place to another.
the area in which the animal is naturally found, the region in which it is endemic.
active during the night
the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.
scrub forests develop in areas that experience dry seasons.
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.
reproduction in which fertilization and development take place within the female body and the developing embryo derives nourishment from the female.
Freitas, S., D. Moraes, R. Santori, R. Cerqueira. 1997. Habitat preference and food use by Metachirus nudicaudatus and Didelphis aurita in a restinga forest at Rio de Janeiro. Revista Brasileira de Biologia, 57(1): 93-98.
Gentile, R., R. Cerqueria. 1995. Movement patterns of five species of small mammals in a Brazilian restinga. Journal of Tropical Ecology, 11(4): 671-677.
Hansen, R., J. Vie, N. Vidal, J. Kervac. 1999. Body measurements on 40 species of mammals from French Guiana. The Zoological Society of London, 247: 419-428.
Hunsaker II, D. 1977. Biology of Marsupials. New York: Academic Press.
Nowak, R. 1997. "Walker's Mammals of the World" (On-line). Accessed Oct. 8, 2001 at http://www.press.jhu.edu/books/walkers_mammals_of_the_world/special.html.
Rodford, K., J. Eisenburg. 1992. Mammals of the Neotropics. Chicago: University of Chicago Press.