The Colla of Quebrada del Toro (i.e. bull's ravine) are descended from native Aymara, Incans and Spaniards. Two towns were studied as part of this collaboration: Gobernador Sola' and Ingeniero Maury, both in the Andean lowlands of northwest Argentina. The population size of the Aymara has been estimated at 2 million, but the size of the Colla sub-population is not known. The Colla have adopted Spanish as their own language. Negotiations with the Argentinean government are ongoing regarding the ownership of the land, but the Colla have de facto control of their pastures and farmland. Crops are privately-owned and operated but the Colla share a common pasture for goats and sheep. Their diet is heavy in corn, squash, sheep and goat meat.  Young boys (10 to 14) also hunt small birds with slingshots for meat. As a largely dry land there are few infectious-parasites and diseases.

The field sites along the Quebrada del Toro ravine were established by Daniel Sznycer, a graduate student at the Center for Evolutionary Psychology at UCSB, for this project. For more information see Raffino (1972) and Tarrago´ 2000.

Ongoing projects include:
    1). The role of physical strength in anger among men and women.
    2). Tests of formidability assessment mechanisms from photographs and voice samples.
    3). Assessing the role of strength on political attitudes about warfare, inequality, and governmental systems.

Papers that have resulted from this collaboration:

Sell, A., Cosmides, L., Tooby, J., Sznycer, D., von Rueden, C. & Gurven, M. (2009).  Human adaptations for the visual assessment of strength and fighting ability from the body and face.  Proceedings of the Royal Society, 276, 575-584.

Sell, A., Bryant, G., Cosmides, L., Tooby, J., Sznycer, D., von Rueden, C., Krauss, A. & M. Gurven (2010).  Adaptations in humans for assessing physical strength and fighting ability from the voice. Proceedings of the Royal Society, in press.

Presentations that have resulted from this collaboration:

Sell, A.  “An evolutionary-computational model of human anger.” Behavior, Evolution and Culture Speaker Series.  Organized by the UCLA Center for Behavior, Evolution, & Culture.  Sept. 2009.

Sell, A. “The Evolutionary Biology of Human Anger.” Understanding and Reducing Aggression, Violence and Their Consequences: Keynote address.  Organized by the Herzliya Symposium on Personality and Social Psychology, March 2009.

Sell, A. “The role of physical strength in anger and anger expressions.” The Evolution of Human Aggression: Lessons for Today’s Conflicts: Keynote address.  Organized by the Barbara L. and Norman C. Tanner Center for Nonviolent Human Rights Advocacy Forum, Feb. 2009.
http://www.cppa.utah.edu//video/flash/Tanner09/Hormones_Aggression/Hormones.html

Sell, A., Tooby, J. & Cosmides, L.  Violent Yells Dissected: Physical Strength is Revealed in the Voice and Enhanced during Anger.  Human Behavior and Evolution Society, College of William and Mary, May 30th - June 3rd, 2007.

Sell, A.  The function of anger expressions: Why does his face look like that?  International Society for Research on Aggression, University of Minnesota, July 25-29, 2006.

Researchers

Aaron Sell Postdoctoral Researcher Center for Evolutionary Psychology University of California, Santa Barbara Santa Barbara, CA 93106, USA (email, website)
Daniel Sznycer Graduate Student Department of Anthropology University of California, Santa Barbara Santa Barbara, CA 93106, USA (email, website)

References