signatures of selection are relatively weak and our segments are short, selectionist interpretations have to be considered with caution. Nevertheless, recent findings point to the evolutionary importance of the cis-acting regulatory elements [Carroll, 2005; Rockman et al., 2005], and our results add to the increasing evidence suggesting that positive selection may be more pervasive in the human population than previously thought [Nielsen, 2005]. ACKNOWLEDGMENTS We thank Dominik Gehl, Herim Vasquez, Alexandru Graziani, and Robert Hamon for development and maintenance of the database and informatics support, as well as Steve Schaffner for his help with the COS1 program. We are indebted to Vania Yotova for drawing haplotype networks, Tina Wambach for her contribu- tion at the early stages of this project, Claude Lanthier for ape blood samples, Eef Harmsen for his interest, and all colleagues who indirectly contributed to this study. 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