The vicuña in the andean altiplano

Abstract

Like its relative the Bactrian camel (Camelus bactrianus) in the deserts of Asia, the vicuña (Vicugna vicugna) thrives in an environment that is beyond the limit for other wild ungulates. In the wild, it is found only in the high elevation altiplano or Puna , an ecoregion of the Andes defined by its sparse steppe vegetation. The vicuña is found in excess at elevations of 3,700 m in a range which extends from 9°30S in Ancash, Peru, to 29° in the III region (Atacama) of Chile (Marn et al., 2007). The rarefied air, long dry season, irregular precipitation, low temperatures with frequent frosts, rugged topography and poor soils create severe limitations for life. However, enough humidity is available to support a unique and specialized ecosystem. Evidence from research in paleoecology and vicuña population genetics indicates that this range was established during the last glacial advance of the Pleistocene and provides important information to understand the way the altiplano environment has changed and how the vicuña has responded to form the patterns that we know today. By helping us to understand the processes that have shaped vicuña evolution this ecological history provides us with a useful framework for conservation decisions. Within this one species, emblematic of a unique ecosystem, the vicuña has many genetic variants, each the product of selective pressures in different parts of the region. As vicuñas live at the limit, such selection pressures must be strong and it is interesting to start by looking at some of the extraordinary adaptations that the vicuña has developed to cope with life in the altiplano.