Doctoral Dissertation Research: East African Middle Stone Age Projectile Technology and Modern Human Behavior

University Of Connecticut, Storrs CT

Investigators

Abstract

Under the supervision of Dr. McBrearty, Veronica Waweru will seek archaeological markers of modern human behavior at the three Kenyan Middle Stone Age (MSA) sites of Cartwright's Site, Prospect Farm, and Prolonged Drift. Determining the age and technological sophistication of the MSA artifacts, and the sources of stone raw material from which they are made, will be the primary goals of the project. There is at present a major debate in anthropology as to whether the earliest members of Homo sapiens in Africa were behaviorally modern. The MSA is significant in this argument because at other African sites it has been shown to contain evidence of sophisticated behaviors, including symbolism, self-adornment, trade networks, and regional differentiation in technology. Genetic and fossil evidence indicates that our species appeared in Africa between 300 ka and 160 ka and the earliest dates for MSA technology indicates that it appeared in the same time interval. A potassium-argon (K/Ar) date of 440 ka for Cartwright's Site, published in 1965 when the method was still in its infancy, far exceeds estimates obtained elsewhere. This project will employ the more accurate and precise 40Ar/39Ar method to establish the age of the site, and thus the time depth of the MSA. Technological complexity, including the use of projectile weaponry, is an important attribute of modern human behavior. The series of technical steps involved in the manufacture and use of the bow and arrow call for complex motor and cognitive skills, and the use of projectile weapons confers the advantage of "death at a distance," facilitating hunting without close confrontation with the quarry. Stone points occur at all three MSA sites that will be examined in this study, but they may have been used to arm short stabbing spears (assegais), long throwing spears (javelins), or arrows. To clarify this issue, the points' aerodynamic properties and traces of damage and use-wear will be examined and compared with a replicated assemblage of stone points with a known history of experimental use. Exchange networks are an aspect of complex behaviour that may have facilitated flexibility in early modern human subsistence strategies. Among contemporary foraging peoples, social relationships with distant trading partners are an important 'insurance policy' during times of local resource failure. This investigation will seek information on MSA exchange networks through analysis of obsidian used in artifact manufacture. The geochemical composition of a sample of obsidian artifacts will be determined through electron microprobe analysis, and compared with a database of the geochemical make-up of obsidian flows in East Africa. This data will serve to determine the sources of the different types of obsidian, the distances they have been traded or transported, and thus the geographic reach of the social networks of the MSA site occupants. This project will continue to foster institutional co-operation by providing opportunities for regional and international students to learn practical fieldwork skills. In the 2003 season, two Ugandan students attached to the British Institute in Eastern Africa were part of the excavation team at Cartwright's site. During the proposed season, one undergraduate geology student in the employ of the National Museum of Kenya (NMK) and a number of local excavators will participate in field work. The project will also train both employed and volunteer students from the University of Nairobi in basic analytical skills at the NMK archaeology laboratory. Results from this study will be disseminated in scientific journals and the University of Connecticut website and will contribute to the body of knowledge regarding the origin and evolution of behavioral complexity in our species.