I am a Paleolithic archaeologist interested in the behavioral evolution of Homo sapiens and the role archaeology can play in understanding the evolutionary success of our species. My primary research area is eastern Africa, where I have directed a number of field projects in Kenya since 2001. My current research focuses on the co-variation of ancient environments and human behavior.
I specialize in the analysis stone tools, and apply a number of geological methods to the archaeological record, particularly the correlation of volcanic ash deposits (tephra) based on micro-scale analyses of their geochemical composition determined using an electron microprobe. In addition to eastern Africa, I work on Paleolithic sites in Turkey and France and continue a long-running involvement in the prehistory of southern New England.