The vicuña (Vicugna vicugna) is found in the Andes of southern Peru, western Bolivia, northwestern Argentina, and northern Chile. At one time it may have occurred as far north as Ecuador. Vicuña inhabit semi-arid rolling grasslands and plains at elevations of 3,500 to 5,750 m. These strikingly graceful animals are able to run at 47 km/hr at an elevation of 4,500 m. They are highly visually oriented animals. (Nowak 1991 and references therein)
The vicuña's head and body length is 1250 to 1900 mm, tail length is 150 to 250 mm, and shoulder height is 700 to 1100 mm. Vicuña range from around 35 to 65 kg. The upperparts are tawny brown, with paler underparts and a white or yellowish red bib on the lower neck and chest. In general form, a vicuña resembles a guanaco (Llama guanicoe), but the vicuña is around 25% smaller, is paler, and lacks both the guanaco's dark face and its callosities ("bumps") on the inner sides of the forelimbs. The lower incisor teeth are unique among living artiodactyls (even-toed hoofed mammals) in that, like rodent teeth, they do not stop growing, with enamel on only one side. (Nowak 1991 and references therein)
The Incas reportedly periodically rounded up vicuña, harvested their wool, and released them, but after the destruction of the Incan Empire vicuña were slaughtered in large numbers for wool and meat. By 1965, their numbers had plummeted to an estimated 6000, but conservation efforts have since allowed significant recovery. (Nowak 1991 and references therein)
The vicuña is one of four South American camelids (mammals in the camel family) recognized today, two of which are wild species, the vicuña and guanaco, 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).
Like the alpaca, the vicuña is strictly a grazer (the guanaco and llama both graze and browse) (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.