Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 5 June 2009:
Vol. 324. no. 5932, pp. 1298 - 1301
DOI: 10.1126/science.1170165
Prev | Table of Contents | Next

Reports

Late Pleistocene Demography and the Appearance of Modern Human Behavior

Adam Powell,1,3 Stephen Shennan,2,3 Mark G. Thomas1,3,*

The origins of modern human behavior are marked by increased symbolic and technological complexity in the archaeological record. In western Eurasia this transition, the Upper Paleolithic, occurred about 45,000 years ago, but many of its features appear transiently in southern Africa about 45,000 years earlier. We show that demography is a major determinant in the maintenance of cultural complexity and that variation in regional subpopulation density and/or migratory activity results in spatial structuring of cultural skill accumulation. Genetic estimates of regional population size over time show that densities in early Upper Paleolithic Europe were similar to those in sub-Saharan Africa when modern behavior first appeared. Demographic factors can thus explain geographic variation in the timing of the first appearance of modern behavior without invoking increased cognitive capacity.

1 Research Department of Genetics, Evolution, and Environment, University College London, Wolfson House, 4 Stephenson Way, London NW1 2HE, UK.
2 Institute of Archaeology, University College London, 31–34 Gordon Square, London WC1H 0PY, UK.
3 Arts and Humanities Research Council (AHRC) Centre for the Evolution of Cultural Diversity, Institute of Archaeology, University College London, 31–34 Gordon Square, London WC1H 0PY, UK.

* To whom correspondence should be addressed. E-mail: m.thomas{at}ucl.ac.uk

Read the Full Text


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
When Ideas Have Sex: The Role of Exchange in Cultural Evolution.
M.W. Ridley (2009)
Cold Spring Harb Symp Quant Biol
   Abstract »    PDF »
On Becoming Modern.
R. Mace (2009)
Science 324, 1280-1281
   Abstract »    Full Text »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)