We thank L. Flynn and an anonymous reviewer for helpful critiques and skillful editing. Field work in the Zinda Pir area of Pakistan was supported by National Geographic Society grants and a PL 480 grant administered through the Smithsonian Institution. The field work in Uganda was supported by the National Science Foundation, the Wenner-Gren Foundation, and the LSB Leakey Foundation. We thank these agencies for their aid. And of course we also thank our late friend W. Downs for his unfailing enthusiasm over many years.