1 Department of Orthopaedic Surgery, University of California, San Francisco, CA 94110; [email protected].
2 Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 02138; Broad Institute of MIT and Harvard University, Cambridge, MA 02142;
3 Department of Human Evolutionary Biology, Harvard University, Cambridge, MA 02138;
4 Department of Anthropology, California Academy of Sciences, San Francisco, CA 94118.