The guanaco (Lama guanicoe) is the largest and most widely distributed wild artiodactyl (even-toed hoofed mammal) in South America. It is the most important native herbivorous species in the South American steppes and the dominant ungulate (hoofed mammal) in a fauna rich in rodents but poor in large mammal species. As of 2006, populations of guanacos were estimated to number a bit under 1 million individuals. As of 2008 guanacos were protected in 22 reserves: 14 in Argentina, 4 in Chile, 3 in Peru, and 1 in Bolivia--leaving only the Paraguayan populations unprotected. (de Lamo et al. 2001; Márin et al. 2008 and references therein)

Although guanacos traditionally played a major role in the lives of some South American aboriginal peoples, populations declined after the introduction of domestic sheep into Patagonia in the early 1900s, largely as a result of conflicts with sheep breeders. Researchers have estimated that there were about 30 to 35 million free-ranging guanacos in South America prior to colonization by Europeans. By the end of the 20th century, this number had dropped to 400,000 to 600,000, distributed over less than half of the historic range (more than 90% of the population is found in Patagonia in Argentina). Montes et al. (2006) proposed the development of sustainable methods for live-trapping and shearing free-ranging guanacos. (Montes et al. 2006 and references therein)

Guanacos are found from sea level to altitudes of about 4500 m in arid, semi-arid, hilly, mountain, steppe, and temperate forest habitats from Peru (8°S) southward to the central eastern and western slopes of the Andes and across Patagonia, including Tierra del Fuego and Navarino Island (de Lamo et al. 2001; González et al. 2006 and references therein).

The guanaco is one of four South American camelids (mammals in the camel family) recognized today, two of which are wild species, the guanaco and the vicuña (Vicugna vicugna), and two of which are domesticated forms, the alpaca (Lama pacos) and the llama (Lama glama). Wild vicuña and guanaco diverged from a shared ancestor two to three million years ago. (Wheeler 1995). At one time it was widely believed that both the domestic alpaca and the llama were derived from guanacos. However, in light of new archaeozoological evidence from 6000 to 7000 years ago in the central Peruvian Andes linking alpaca origins to the vicuña, Kadwell et al. (2001) investigated the origins of these domesticated forms using mitochondrial and nuclear DNA markers. Their results supported the hypothesis that the alpaca is derived from the vicuña (and confirmed the hypothesis that the llama is derived from the guanaco), although this work also revealed genetic evidence of historical hybridization and gene flow (at least among domesticated forms). Chromosomal analyses have also indicated that the llama was derived from the guanaco and the alpaca from the vicuña (Marín et al. 2007). Given the well established divergence between the guanaco and vicuña, many authors suggest that the correct name for the alpaca is therefore Vicugna pacos (Kadwell et al. 2001; Marín et al. 2007).

The guanaco (Lama guanicoe) is the largest and most widely distributed wild artiodactyl (even-toed hoofed mammal) in South America. It is the most important native herbivorous species in the South American steppes and the dominant ungulate (hoofed mammal) in a fauna rich in rodents but poor in large mammal species. As of 2006, populations of guanacos were estimated to number a bit under 1 million individuals. As of 2008 guanacos were protected in 22 reserves: 14 in Argentina, 4 in Chile, 3 in Peru, and 1 in Bolivia--leaving only the Paraguayan populations unprotected. (de Lamo et al. 2001; Márin et al. 2008 and references therein)

Although guanacos traditionally played a major role in the lives of some South American aboriginal peoples, populations declined after the introduction of domestic sheep into Patagonia in the early 1900s, largely as a result of conflicts with sheep breeders. Researchers have estimated that there were about 30 to 35 million free-ranging guanacos in South America prior to colonization by Europeans. By the end of the 20th century, this number had dropped to 400,000 to 600,000, distributed over less than half of the historic range (more than 90% of the population is found in Patagonia in Argentina). Montes et al. (2006) proposed the development of sustainable methods for live-trapping and shearing free-ranging guanacos. (Montes et al. 2006 and references therein)

Guanacos are found from sea level to altitudes of about 4500 m in arid, semi-arid, hilly, mountain, steppe, and temperate forest habitats from Peru (8°S) southward to the central eastern and western slopes of the Andes and across Patagonia, including Tierra del Fuego and Navarino Island (de Lamo et al. 2001; González et al. 2006 and references therein).

The guanaco is one of four South American camelids (mammals in the camel family) recognized today, two of which are wild species, the guanaco and the vicuña (Vicugna vicugna), and two of which are domesticated forms, the alpaca (Lama pacos) and the llama (Lama glama). Wild vicuña and guanaco diverged from a shared ancestor two to three million years ago. (Wheeler 1995). At one time it was widely believed that both the domestic alpaca and the llama were derived from guanacos. However, in light of new archaeozoological evidence from 6000 to 7000 years ago in the central Peruvian Andes linking alpaca origins to the vicuña, Kadwell et al. (2001) investigated the origins of these domesticated forms using mitochondrial and nuclear DNA markers. Their results supported the hypothesis that the alpaca is derived from the vicuña (and confirmed the hypothesis that the llama is derived from the guanaco), although this work also revealed genetic evidence of historical hybridization and gene flow (at least among domesticated forms). Chromosomal analyses have also indicated that the llama was derived from the guanaco and the alpaca from the vicuña (Marín et al. 2007). Given the well established divergence between the guanaco and vicuña, many authors suggest that the correct name for the alpaca is therefore Vicugna pacos (Kadwell et al. 2001; Marín et al. 2007).

Guanacos are around 100 to 120 kg, with slender limbs and neck. The upper parts are dark fawn brown, the underparts are white, and the face is blackish. The wooly coat is longest on the flanks, chest, and thighs. Females have four mammae. (Nowak 1991 and references therein)

Like the llama, the guanaco feeds by both grazing and browsing (the vicuña and alpaca are strictly grazers) (Nowak 1991 and references therein).

Di Rocco et al. (2010) published a comparative analysis of the complete mitochondrial genome of the guanaco and the mitochondrial coding sequence of the vicuña.

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.

Biogeographic Regions: neotropical (Native )

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.

Range mass: 115 to 140 kg.

• Terrestrial

Guanacos inhabit grasslands and shrublands from sea level to 4,000m. Occasionally they winter in forests.

Terrestrial Biomes: desert or dune ; savanna or grassland ; mountains

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.

Average lifespan

Status: captivity: 28.3 years.

Average lifespan

Status: wild: 20.0 years.

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.

Average birth mass: 11500 g.

Average gestation period: 335 days.

Average number of offspring: 1.

Average age at sexual or reproductive maturity (male)

Sex: male: 730 days.

Average age at sexual or reproductive maturity (female)

Sex: female: 365 days.

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.

IUCN Red List of Threatened Species: least concern

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.