The Evolution of the Indian Ocean and the Origin of Primates – lundi 8 avril 2019, 14h30 Amphi A
Living non-human primates inhabit the forests and woodlands of South and Central America, Africa, Madagascar, India and Sri Lanka, and south-east Asia as far north as Japan. Their current ranges are often separated by vast tracts of ocean or hostile environment. The date estimated by molecular data for the origin of the primate order is latest Cretaceous, approximately 75 Ma, although the oldest recognisably primate fossils have been found in theHigh Atlas Mountains of Morocco, and date to 60 Ma. How primates came to occupy their current distributions has been an issue of great interest and debate among primate evolutionary biologists. The strepsirrhine (or tooth-combed) primates in particular occupy a range that borders on much of the Indian Ocean, and it is difficult to believe that the formation of the ocean was unrelated to the evolution of these primates. In this talk I discuss the timing of important events in early primate evolution, and the fossils that testify to these events. Primates appear to have evolved long after major sundering events in the break-up of the continents occurred, particularly those involving the Indian Ocean margins. This has led to a general belief that primates rafted across oceans, both from Africa to South America, and from Africa to Madagascar, in order to generate their current biogeographic pattern. I shall investigate the likelihood of these scenarios, and seek alternative explanations for these patterns.