Abstract

This review examines the evolutionary and biogeographic history of South American camelids, which include the wild species guanaco (Lama guanicoe) and vicu & ntilde;a (Vicugna vicugna), and their domestic counterparts, llama (L. glama) and alpaca (V. pacos). We trace their origins within the Camelidae family, which appeared in North America approximately 46 million years ago. This family experienced at least four major radiation events during the Eocene and Miocene, culminating in the diversification of the subfamily Camelinae into the tribes Camelini and Lamini. The ancestors of South American camelids emerged from the Lamini tribe, dispersing into South America and surviving the widespread extinctions that affected many Camelidae during the Late Pleistocene and Early Holocene. This paper reevaluates the taxonomic classification of the Lamini using both paleontological and molecular evidence, with a specific focus on the lineages that led to the modern South American species. We also explore how environmental changes-particularly climatic shifts following the Last Glacial Maximum and the expansion of modern humans-have shaped the biomes inhabited by these unique camelids. This analysis provides a comprehensive overview of the key evolutionary milestones that have defined the unique history of this iconic group.