Pleistocene human dispersals: climate, ecology and social behavior

JOSÉ LUIS LANATA, SERGI LOZANO, BIENVENIDO MARTÍNEZ-NAVARRO

Burgos

Simposio; XVII World UISPP Congress 2014; 2014

XVII World UISPP Congress 2014

The modern history of thinking about the origin of species has been dominated by the relationship between environments (and their changes) and the process of speciation. Darwin?s original argument for evolution by means of natural selection (Darwin 1859) is an ecological argument: species ?adapt? to their physical and biotic environments. Those best adapted to their environment survive and leave more descendants than those that are less adapted. This reasoning clearly works on biological, even paleontological terms. But, does it work on social and cultural ones? And, if it does, how? This working session will evaluate this question in the context of human evolution, by discussing different cases in all the continents.The research on the human dispersals out of Africa, into Eurasia, Australia and the Americas, has changed the ideas about chronologies and the ecological scenarios where humans were able to colonize new territories with new environments in different and, sometimes, inhospitable climates with marked seasonality.The oldest human record in Eurasia is found in Dmanisi (Georgia, Caucasus), dated 1.85 Ma, during the Olduvai normal chron. The fossil record of Eurasia reveals an important faunal turnover at this moment and also the arrival of several large mammals? species of African origin, chronologically coincidental with this human dispersal. Later, different speciation waves and other subsequent dispersals into Eurasia of fauna and hominins are coincidental during the Pleistocene. This geographic theatre increases when the megafaunal extinction around the planet -Eurasia, Australia and the Americas- can be related with the expansion of early modern humans, Homo sapiens, to these territories.Climate changes, faunal turnovers, and human dispersals into new continents, seem to be coincidental. What is not so clear is how and to what degree social and cultural human evolution interacted with them. At this sense, an important question is to explain the effect of the increasing of sociality in early and more recent humans in order to be more successful during the global dispersal process, in competence with other faunal species and/or human populations