Cynthia Beall is an American physical anthropologist at the Case Western Reserve University, Cleveland, Ohio. Four decades of her research on people living in extremely high mountains became the frontier in understanding human evolution and high-altitude adaptation. Her groundbreaking works among the Andean, Tibetan and East African highlanders are the basis of our knowledge on adaptation to hypoxic condition and how it influences the evolutionary selection in modern humans. She is currently the Distinguished University Professor, and member of the U.S. National Academy of Sciences and the American Philosophical Society.