Jonathan H. Turner is 38th University Professor of the University of California System; Research Professor, University of California, Santa Barbara, and Distinguished Professor at the University of California, Riverside. He is also Director of the Institute for Theoretical Social Science, Santa Barbara, CA, USA. He is the author of hundreds of research articles and the author of more than 40 distinguished books, including most recently, The New Evolutionary Sociology (with Richard Machalek). Richard Machalek is Professor Emeritus of Sociology at the University of Wyoming. His work addresses the evolution of social behavior among both human and non-human species. He analyzes phenomena such as the evolution of societal complexity among both humans and the eusocial insects, the evolution of expropriative social behaviors across species lines, emergent properties of both human and nonhuman societies, the evolved human psychology implicated in reciprocity and exchange, and theoretical points of convergence and divergence between sociology and sociobiology. His publications have appeared in venues such as Sociological Theory, the American Journal of Sociology, Advances in Group Processes, Rationality and Society, Advances in Human Ecology and various encyclopedias, handbooks, and other edited volumes. He is co-editor (with Jonathan H. Turner and Alexandra Maryanski) of Handbook on Evolution and Society: Toward an Evolutionary Social Science (Routledge).