1. Department of Anthropology, University of Pennsylvania , Philadelphia, PA 19104 , USA
2. Department of Anthropology, Rutgers, the State University of New Jersey , New Brunswick, NJ 08901 , USA
3. Proceedings of the National Academy of Sciences , Washington, DC 20001 , USA
4. Department of Anthropology & Carolina Population Center, University of North Carolina at Chapel Hill , Chapel Hill, NC 27599 , USA
5. Division of Gastroenterology, Hepatology and Nutrition, The Children's Hospital of Philadelphia , Philadelphia, PA 19104 , USA
6. Department of Pediatrics, The University of Pennsylvania Perelman School of Medicine , , Philadelphia, PA 19104 , USA
7. Department of Anthropology, Lakehead University , Thunder Bay, ON P7B 5E1 , Canada
8. Human Origins Program, Department of Anthropology, National Museum of Natural History, Smithsonian Institution , Washington, DC 20013 , USA
9. Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage, University of Wollongong , Wollongong NSW 2522 , Australia