Sarah Mathew is an Assistant Professor in the School of Human Evolution and Social Change at Arizona State University. She is an evolutionary anthropologist who combines formal models and field studies to explore how humans evolved the capacity to cooperate in large groups of genetically unrelated individuals. She has conducted in depth field studies among Turkana pastoralists in Kenya examining why warriors risk their life in warfare, which has illuminated the role of moral sanctioning and cultural evolutionary processes in maintaining cooperation in small-scale societies. Currently she is spearheading an empirical study among the Turkana and other small-scale societies to examine what is the scale of cooperation, group-beneficial norms and moral sanctioning mechanisms. This research program will help provide a more detailed picture of the extent to which the cultural boundary is also the moral boundary, data that will be critical for evaluating theories of how culture enabled human cooperation. She was among thirty one scholars nationwide who were recently awarded the Andrew Carnegie fellowship in recognition of work that would contribute towards a better understanding of the challenges facing democracy and international order.