Found from southern Peru down the Andean zone of Chile and Argentina to Tierra del Fuego and Navarino Island. There is also a population in far western Paraguay.
Guanacos inhabit grasslands and shrublands from sea level to 4,000m. Occasionally they winter in forests.
They stand at 1,100 to 1,200mm at the shoulder and have slender bodies with long limbs and neck. The head is typical of camelids with long, pointed ears and cleft, highly mobile lips. Their fur can be long, thick and wooly, especially along the flanks, chest and thighs. It is reddish-brown dorsally, and the underparts are white.
Females are apparently induced ovulators, and especially in the southern end of the range breeding reaches a peak in February. Young are born in December to February after an eleven month gestation period. They weigh 8-15kg at birth and nurse for eleven to fifteen months. Females may begin to breed as early as one year of age, sometimes younger, though two to three years old is more typical.
There are three types of social groups: family groups, male troops, and solitary males. A family band is composed of a single breeding male, several females, and offspring. Males limit the size of their group by driving out young males of six to twelve months and driving off males and sometimes females trying to enter the group. Males defend a territory that the group resides on, and the territory is demarcated by large communal defecation piles. Only about 18% of males are in a family group; the others are in bands or solitary. The all-male bands are generally made up of young males. Males in these herds learn fighting ability through play fights. The solitary males tend to be mature males looking for females or herds to take over.
Guanacos are herbivores that can inhabit dry areas and forego drinking for long periods. They are versatile foragers, both browsing and grazing on grasses and plants.
Guanacos have long been hunted for their meat and fur. They are believed to be the ancestor to the now domesticated llamas and alpacas, which are important as beasts of burden and for their fur.
Guanacos have had their numbers drastically reduced due to human pressures of habitat encroachment, habitat destruction, and hunting. In addition, climatic changes are also blamed for decreases in population size and range.
Guanacos when young are vulnerable to pumas, but the reduction in the puma populations has lead to mortality due to starvation.
Adult guanacos can run at speeds of up to 56km/hr.
Anna Bess Sorin (author), Biology Dept., University of Memphis.
living in the southern part of the New World. In other words, Central and South America.
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
in deserts low (less than 30 cm per year) and unpredictable rainfall results in landscapes dominated by plants and animals adapted to aridity. Vegetation is typically sparse, though spectacular blooms may occur following rain. Deserts can be cold or warm and daily temperates typically fluctuate. In dune areas vegetation is also sparse and conditions are dry. This is because sand does not hold water well so little is available to plants. In dunes near seas and oceans this is compounded by the influence of salt in the air and soil. Salt limits the ability of plants to take up water through their roots.
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.
having the capacity to move from one place to another.
This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.
the area in which the animal is naturally found, the region in which it is endemic.
reproduction that includes combining the genetic contribution of two individuals, a male and a female
uses touch to communicate
A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.
A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.
A terrestrial biome found in temperate latitudes (>23.5? N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.
Redford, K.H. and J.F. Eisenberg. 1992. Mammals of the Neotropics. University of Chicago Press: Chicago.
Nowak, R.M. and J.L.Paradiso. 1983. Walker's Mammals of the World 4th Ed. Johns Hopkins University Press: Baltimore.