Evolution of South American Mammals: An Analysis by Prothero

The article analyzes the unique evolutionary history of mammals in South America, which served as a biological laboratory for millions of years during the Cenozoic. The author describes the phenomenon of convergence, through which native groups such as Notoungulata and Litopterna developed forms resembling modern ungulates despite a lack of close kinship. Particular attention is paid to the taxa Toxodon and Macrauchenia, whose enigmatic systematic position was only resolved thanks to paleoproteomics. Analysis of type I collagen sequences revealed their belonging to the Panperissodactyla lineage, linking them to horses and rhinoceroses. The text emphasizes the role of modern research methods in distinguishing actual genetic links from superficial anatomical similarities resulting from adaptation to similar ecological niches.