Holocene Climate and Cultural Changes in the Atacama Desert
by
Martin Grosjean
NCCR Climate, University of Bern, 9a Erlachstrasse, CH-3012 Bern, Switzerland
Coauthors: Lautaro Núñez A. (Instituto de Investigaciones Arqueológicas y Museo R.P. Gustavo Le Paige, Universidad Católica del Norte, Chile) and Isabel Cartajena (Departamento de Antropología ,Universidad de Chile, Chile).

Initial human colonization of the Central Andes in the Atacama Desert around 13 cal kyr B.P. coincided with a rapid change from extremely arid to humid environments. Hostile extremely arid environments prior to this time may explain why human occupation of the Atacama Desert lagged ca. 2500 years behind first occupations in Central Chile/Patagonia.

Favourable environments (13–9 cal kyr B.P.) sustained highly mobile groups of hunters in diverse habitats from the Pacific coast up to the Puna (4000 m). Co-existence with Pleistocene fauna is evidenced until 11 cal kyr B.P. Paleoindian ‘Fell’ occupation has been found and 14C-dated to that time. This supports the existence of a Pacific route for early cultures.

Following a dramatic regression of paleolakes around 9 cal kyr B.P., people dispersed between ca. 9-4.5 cal kyr B.P. This collapse of widespread occupation (‘Silencio Arqueologico’) reflects environmental stress. During that time, people occupied alternative habitats (‘ecological refuges’) where resources remained available in the overall harsh environment. Domestication of camelids and the diversification of the lithic industry fell into this period.

The second phase of human occupation (ca. 4 cal kyr B.P.) coincided with the recuperation of lake levels and brought innovative irrigated agriculture and pottery. Little is known about the environmental evolution of the last 1000 years.

The site-by-site geoecological assessment revealed that regional climatic aridity stress does not necessarily translate into local environmental stress, with shortage of water, animal and vegetation resources. We found sites with (i) a direct response to climatic stress (paleoshoreline sites), (ii) sites with an indifferent response to climatic stress (large river and spring sites), and (iii) sites with an inverse response to climatic stress, where arid conditions created paradoxically better habitats (eg. ecological refuges). This calls for a broader concept of the ‘silencio arqueológico’.

Date received: December 6, 2004

Copyright © 2004 by the author(s). The author(s) of this document and the organizers of the conference have granted their consent to include this abstract in Atlas Conferences Inc. Document # caod-58.