Young Darwin and the ecology of South American fossil mammals

VIZCAÍNO S. F.; FERNICOLA J. C.; FARIÑA R. A.

Revista de la Asociación Geológica Argentina

Asociación Geológica Argentina

Año: 2009 vol. 64 p. 160 - 169

0004-4822

During his two years in South America Charles Darwin became fascinated not only with the lush vegetation of Brazil, but also with the gigantic Pleistocene mammals that he found in the drier areas of Uruguay, and in the pampas and Patagonian coast of Argentina. These findings included various ground sloths and glyptodonts among xenarthrans, and hoofed herbivores like Toxodon and Macrauchenia, in addition to horses and small rodents. He concluded that the general assumption that large animals require luxuriant vegetation was false and that vitiated the reasoning of geologists on some aspects of Earth´s history. He also reflected on the evident changes that occurred in the continent, the extinct fauna of which suggested to him an analogy to southern parts of Africa. He wondered about our ignorance of biological traits in extinct creatures and the reasons for their extinction. Thus, not only did Darwin inspire phylogenetic studies on fossil mammal lineages, he also opened a gate to the research on their behaviour, physiology and extinction; i.e., their palaeobiology. Whereas the first approach was largely developed in South America beginning about the second half of the 19th century due to the intellectual influence of Florentino Ameghino, palaeobiology became a much more recent line of work, in apparent relation to innovations in methodology and technology. This contribution provides an overview of recent contributions on the palaeobiology of Pleistocene fossil mammals of South America as attempts to provide answers for Darwin´s questions.