Hunter-Gatherer Persistence and Demography in Patagonia (Southern South America): The Impact of Ecological Changes during the Pleistocene and Holocene

The results of this chapter suggest that hunter-gatherers from northwest and south Patagonia were resilient to the significant ecological changes that took place during the Late Pleistocene and Early Holocene. In particular, the rate of population growth was resistant to reduction in the diversity of available resources as a consequence of megafaunal extinctions around 10 000 BP. The resistance of hunter-gatherers from northwest and south Patagonia could be related to the ability of human populations to absorb the impact of relatively slow ecological changes. The chronological association between the demographic dynamics and archaeological evidence suggests that cultural responses (i.e., technological changes) might have helped maintain and even increase human population density. Thus, the two populations used ecological adaptations as a way to maintain, and even grow, effective population sizes during a period of ecological turnover.Despite evidence for population growth during the Pleistocene?Holocene transition, the human populations living in these two regions responded in different ways to megafaunal extinctions. Populations in south Patagonia persisted through a low but constant rate of population growth that mirrored the demographic expansion of highly valued prey. The northwestern population experienced a faster rate of growth, probably sustained by an increase in the carrying capacity of the environment mediated by cultural changes that expanded dietary breadth. These results demonstrate that demographic resilience is mediated by differing modes of cultural adaptation to environmental challenges.