1. Department of Anthropology, Washington University in St Louis, St Louis, MO 63130, United States of America
2. Department of Anthropology, University of Virginia, Charlottesville, VA 22904-4120, United States of America
3. Institute of Anthropology, Gender and African Studies, University of Nairobi, PO Box 30197-00100, Nairobi, Kenya
4. Archaeology Section, Earth Sciences Department, National Museums of Kenya, PO Box 40658-00100, Nairobi, Kenya
5. Academy of Lifelong Learning, Western Washington University, Bellingham, WA 98225, United States of America