1. Center for Human Evolutionary Studies, Department of Anthropology, 131 George Street, Rutgers University, New Brunswick, NJ 08901–1414, USA.
2. Department of Anthropology and Institute of Ecology, Baldwin Hall, University of Georgia, Athens, GA 30602–1619, USA.
3. Paleo-Cultural and Environmental Research, Post Office Box 70566, Dar es Salaam, Tanzania.
4. School of Anatomical Sciences, University of the Witwatersrand Medical School, 7 York Road, Parktown 2193, Johannesburg, South Africa.
5. Berkeley Geochronology Center, 2455 Ridge Road, Berkeley, CA 94709, USA.
6. Department of Geosciences, University of Arizona, Tucson, AZ 85718, USA.
7. Department of Geological Sciences, Rutgers University, Piscataway, NJ 08854, USA.
8. Department of Earth Sciences, University of Liverpool, Brownlow Street, Post Office Box 147, Liverpool L69 3BX, UK.
9. Human Origins Program, National Museum of Natural History, Smithsonian Institution, Washington, DC 20560–0112, USA.
10. Archaeology Department, University of Cape Town, 7700 Rondebosch, Cape Town, South Africa.
11. Department of Mineral Sciences, National Museum of Natural History, Smithsonian Institution, MRC 119, Washington, DC 20560–0119, USA.
12. Ebert & Associates, 3700 Rio Grande Boulevard N.W., Suite 3, Albuquerque, NM 87107, USA.