Robert Boyd

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Robert Boyd

Distinguished Professor Emeritus


Phone: 310-909-3156

Personal Website

Curriculum Vitae

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Unlike other organisms, humans acquire a rich body of information from others by teaching, imitation, and other forms of social learning, and this culturally transmitted information strongly influences human behavior. Culture is an essential part of the human adaptation, and as much a part of human biology as bipedal locomotion or thick enamel on our molars. My research is focused on the evolutionary psychology of the mechanisms that give rise to and shape human culture, and how these mechanisms interact with population dynamic processes to shape human cultural variation. I have done much of this work in collaboration with Peter J. Richerson.

Our 2005 book entitled Not by Genes Alone: How culture transformed human evolution gives a nonmathematical treatment of this work, and is now available from the University of Chicago Press. Read Chapter 1. Here is an NPR interview with a brief account of our ideas about cultural evolution (Mpeg3)

Richard McElreath and I have a book entitled Mathematical Models of Social Evolution: A guide for the perplexed available from University of Chicago Press. Table of Contents


C. Perreault, C. Moya, and R. Boyd. A Baysian approach to the evolution of social learning. Evolution and Human Behavior, Proofs posted online April 2012 (pdf.

J. Henrich, R. Boyd, and P. J. Richerson. The puzzle of monogamous marriage, Philosophical Transactions of the Royal Society (B), 367, 657–669, 2012 (pdf).

R. Boyd, P. J. Richerson, and J. Henrich. The cultural niche: Why social learning is essential for human adaptation, Proceedings of the National Academy of Sciences (USA) 108: 10918–10925, 2011 (pdf). Commentary: Discover,

Mathew, S. and R. Boyd. Punishment sustains large-scale cooperation in prestate warfare. Proceedings of the National Academy of Sciences (USA)108: 11375–11380, 2011, (pdf). Supporting Information (pdf). Commentary: Richard McElreathDiscoverNew ScientistPublico.esBaumard and Liénard, and our reply to Baumard and Liénard.

Boyd, R., P. J. Richerson, and J. Henrich. Rapid cultural adaptation can facilitate the evolution of large-scale cooperation, Behavioral Ecology and Sociobiology, 65:431–444, 2011 (pdf).

Boyd, R. Primed for reading, a review of Reading and the Brain by Stanislas Dehaene, PLoS Biology, 8:1–2, 2010, (pdf).

Boyd, R. and P. J. Richerson. Transmission coupling mechanisms: cultural group selection. Philosophical Transactions of the Royal Society (B), 365, 3787-3795, 2010, (pdf).

Kline, M. and R. Boyd, Population size predicts technological complexity in oceania, Proceedings of the Royal Society (B), 277, 2559–2564, 2010, (pdf) a Science story about the paper (pdf), and a Matt Ridley column in the Wall Street Journal (pdf).

Richerson, P. J., R. Boyd, and J. Henrich, Gene-culture coevolution in the age of genomics, Proceedings of the National Academy of Sciences (USA), 107, 8985–8992, 2010. (pdf)

Boyd, R., H. Gintis, and S. Bowles, Coordinated punishment of defectors sustains cooperation and can proliferate when rare, Science, 328, 617-620, 2010. (pdf) (html)

Rendell, L., R. Boyd, D. Cownden, M. Enquist, K. Eriksson, M. W. Feldman, L. Fogarty, S. Ghirlanda, T. Lillicrap, and K. N.Laland, Why copy others? Insights from the social learning strategies tournament, Science, 328, 208-213, 2010. (pdf) (html)

R. Boyd and P. J. Richerson, Culture and the evolution of human cooperation, Philosophical Transactions of the Royal Society (B), 364:3281-3288, 2009. (pdf)

Richerson, P. J, R. Boyd, and R.L. Bettinger, Cultural Innovations and Demographic Change, Human Biology, 81, 211–235, 2009. (pdf)

Boyd, R. Does an evolutionary perspective help understand environmental degradation? Trends in Ecology and Evolution, 24: 72, 2009. (pdf)

Boyd, R. and P. J. Richerson, Voting with your feet: Payoff biased migration and the evolution of group beneficial behavior, Journal of Theoretical Biology, 257: 331-339, 2009. (pdf)

Mathew, S. and R. Boyd. When does optional participation allow the evolution of cooperation? Proceedings of the Royal Society (B). 276:1167-1174, 2009. (pdf)

P. J. Richerson and R. Boyd, Migration: An Engine for Social Improvement, Nature, 456: 18, 2008. (pdf)

J. Henrich and R. Boyd, Division of Labor, Economic Specialization and the Evolution of Social Stratification, Current Anthropology, 49: 715-724, 2008. (pdf) Online enhancements (pdf).

R. Boyd and P. J. Richerson. Gene-Culture Coevolution and the Evolution of Social Institutions, In: Better than Conscious? Decision Making, the Human Mind, and Implications for Institutions. C. Engel and W. Singer eds, MIT Press, Cambridge. Pp 305-324, 2008. (pdf)

J. Henrich, R. Boyd, and P. J. Richerson. Five Misunderstandings about Cultural Evolution. Human Nature, 19: 119–137, 2008. (pdf)

R. Boyd and S. Mathew. A Narrow Road to Cooperation, Science, 316: 1858–1859, 2007. (pdf).

S. Le and R. Boyd, Evolutionary Dynamics of the Continuous Iterated Prisoner’s Dilemma, Journal of Theoretical Biology, Volume 245, 258–267. 2007, (pdf).

R. Boyd. The Puzzle of Human Sociality, Science, 314: 1553 2006. (pdf)

R. Boyd and P. J. Richerson. Culture, Adaptation, and Innateness. In: The Innate Mind: Culture and Cognition, P. Carruthers, S. Stich, & S. Laurence, eds., 2006.(pdf).

R. Boyd. Reciprocity: You have to think different. Journal of Evolutionary Biology, 19, 1380–1382. (pdf).

R. Boyd and P. J. Richerson. Culture and the evolution of the human social instincts. In: Roots of Human Sociality, S. Levinson and N. Enfield, eds., Berg, Oxford. 2006, (pdf)

R. Boyd and P. J. Richerson, Solving the Puzzle of Human Cooperation, In: Evolution and Culture, S. Levinson ed. MIT Press, Cambridge MA, pp 105–132, 2005(pdf).

J. Henrich, R. Boyd, S. Bowles, C. Camerer, E. Fehr, H. Gintis, R. McElreath, M. Alvard, A. Barr, J. Ensminger, K. Hill, F. Gil-White, M.Gurven, F. Marlowe, J. Q. Patton, N. Smith, and D. Tracer, ‘Economic Man’ in Cross-cultural Perspective: Behavioral Experiments in 15 Small-scale Societies, Behavioral and Brain Sciences, 28: 795–855, 2005. (pdf)

K. Panchanathan and R. Boyd. Indirect reciprocity can stabilize cooperation without the second-order free rider problem. Nature 432: 499–502, 2004. (pdf). Accompanying News & Views commentary by Ernst Fehr (pdf).

K. Panchanathan and R. Boyd. A Tale of Two Defectors: The Importance of Standing for the Evolution of Indirect Reciprocity. Journal of Theoretical Biology, 224:115–126, 2003, (pdf).

H. Gintis, S. Bowles, R. Boyd, & E. Fehr, Explaining Altruistic Behavior in Humans, Evolution and Human Behavior, 24: 153–172, 2003, (pdf).

P. J. Richerson, R. Boyd, and J. Henrich. The Cultural Evolution of Human Cooperation. The Genetic and Cultural Evolution of Cooperation, P. Hammerstein ed. MIT Press, Cambridge MA, 2003, pp 357–388 (pdf). This paper was presented at a Dahlem Conference, June 2002.

R. Boyd, H. Gintis, S. Bowles, and P. J. Richerson. The Evolution of Altruistic Punishment. Proceedings of the National Academy of Sciences (USA) 100: 3531–3535, 2003 (pdf). Visual Basic 5 files used for simulation (.zip)

R. McElreath, R. Boyd and P. J. Richerson. Shared Norms Can Lead to the Evolution of Ethnic Markers. Current Anthropology, 44: 122–130, 2003(pdf).

J. Henrich and R. Boyd, Culture and Cognition: Why Cultural Evolution Does Not Require Replication of Representations, Culture and Cognition, 2: 87–112, 2002. (pdf).

P. J. Richerson, R. Boyd and B. Paciotti. An Evolutionary Theory of Commons Management, The Drama of the Commons. Elinor Ostrom, Thomas Dietz, Nives Dolsak, Paul C. Stern, Susan Stonich, and Elke U. Weber, Eds., National Academy Press, Washington, D.C. 2002. pp 413–413 (pdf).

R. Boyd and P. J. Richerson, Group Beneficial Norms Spread Rapidly in a Structured Population, Journal of Theoretical Biology, 215: 287–296, 2002.(pdf).

P. J. Richerson and R. Boyd. Built for Speed, Not for Comfort, Darwinian Theory and Human Culture, History and Philosophy of the Life Sciences, 23: 425–465 (pdf).

R. Boyd and P. J. Richerson, Norms and Bounded Rationality. In: The Adaptive Tool Box, G. Gigerenzer and R. Selten, eds. pp 281–296, MIT Press, Cambridge MA, 2001. Abstract (html)

J. Henrich and R. Boyd, Why people punish defectors: Weak conformist transmission can stabilize costly enforcement of norms in cooperative dilemmas. Joural of Theoretical Biology, 208: 79–89. 2001 (pdf).

P. J. Richerson, R. Boyd, and R. L. Bettinger, Was Agriculture Impossible During the Pleistocene but Mandatory during the Holocene? A Climate Change Hypothesis, American Antiquity 66: 387–411, 2001 (pdf).

J. Henrich, R. Boyd, S. Bowles, C. Camerer E. Fehr, H. Gintis, and R. McElreath, Cooperation, Reciprocity and Punishment in Fifteen Small-scale Societies, American Economic Review, 91: 73–78, 2001(pdf).

J. B. Silk, E. Kaldor, and R. Boyd, Cheap Talk When there are Conflict of Interest. Animal Behaviour, 59: 423-432, 2000 (pdf).

R. Boyd and P. J. Richerson, Memes: Universal Acid or a Better Mouse Trap. In: Darwinizing Culture: The Status of Memetics as a Science. R. Aunger ed. pp.143–162, Oxford University Press, Oxford. 2000 (pdf).

P. J Richerson and R. Boyd, The Evolutionary Dynamics of a Crude Super Organism. Human Nature, 10: 253–289, 1999 (pdf).

J. Henrich and R. Boyd, The Evolution of Conformist Transmission and the Emergence of Between-Group Differences.Evolution and Human Behavior,19: 215–242. 1998 (pdf).

P. J. Richerson and R. Boyd, The Evolution of Human Ultra-SocialityIn: Ideology, Warfare, and Indoctrinability. I. Eibl-Eibisfeldt and F. Salter, eds. pp. 71–95, Berghan Books, 1998 (pdf).

R. Boyd, P.J. Richerson, M. Borgerhoff-Mulder, and W. H. Durham. Are Cultural Phylogenies Possible? In: Human by Nature, Between Biology and the Social Sciences, P. Weingart, P.J. Richerson, S.D.Mitchell, and S. Maasen, eds. Lawrence Erlbaum Associates: Mahwah, NJ, 1997. Pp. 355–386 (pdf).

R. Boyd and P. J. Richerson, Why Culture is Common but Cultural Evolution is Rare, Proceedings of the British Academy, 88: 73–93, 1996(pdf).

J. Soltis, R. Boyd and P. J. Richerson, Can Group-functional behaviors evolve by cultural group selection? An empirical test. Current Anthropology, 63: 473–494, 1995 (pdf).

R. Boyd. The evolution of reciprocity when conditions vary. In: Coalitions and Alliances in Humans and Other Animals, A. Harcourt and F DeWaal, eds., Oxford University Press, NY, 1992 (pdf).

R. Boyd and P. J. Richerson, Group Selection Among Alternative Evolutionarily Stable Strategies, Journal of Theoretical Biology, 145: 331-342, 1990. (pdf)

R. Boyd and P. J. Richerson, Why Does Culture Increase Human Adaptability? Ethology and Sociobiology. 16: 125–143, 1995 (pdf).

R. Boyd and P. J. Richerson, Punishment Allows the Evolution of Cooperation (or Anything Else) in Sizable Groups, Ethology and Sociobiology, 13: 171-195, 1992 (pdf).

R. Boyd, Mistakes allow evolutionary stability in the repeated prisoner’s dilemma game, Journal of Theoretical Biology, 136, 47–56, 1989 (pdf).

R. Boyd and P. J. Richerson, The Evolution of Indirect Reciprocity, Social Networks, 11: 213-236, 1989 (pdf).

R. Boyd and P. J. Richerson, The Evolution of Reciprocity in Sizable Groups, Journal of Theoretical Biology, 132: 337-356, 1988.(pdf).

R. Boyd and P. J. Richerson, The Evolution of Ethnic Markers, Cultural Anthropology, 2: 65–79, 1987. (pdf)

R. Boyd and J. P. Lorberbaum, No Pure Strategy is Stable in the Repeated Prisoner’s Dilemma Game, Nature, 327: 58–59, 1987, (pdf)

R. Boyd and P. J. Richerson, Why is Culture Adaptive? Quarterly Review of Biology, 58: 209–214, 1983. (pdf)

R. Boyd, Density-dependent Mortality and the Evolution of Social Interactions, Animal Behaviour 30: 972-982, 1982, (pdf).

R. Boyd and P. J. Richerson, Effect of Phenotypic Variation on Kin Selection, Proceedings of the National Academy of Sciences (USA), 77: 7506-7509, 1980. (pdf)

Graduate Students

Former Students

Francisco Gil-White The evolutionary psychology of ethnicity. Field work in Mongolia. PhD 2001. Formerly Assistant Professor of Psychology, University of Pennsylvania. Now investigative journalist. Joe Henrich The evolution of group differences, and the evolutionary psychology of prestige. Subsistence ecology. How do people learn to cope with their environments? Norms and cooperation, evolution of religion. Field work in Fiji. PhD 2000. Currently: Canadian Research Professor, Departments of Psychology and Economics, University of British Columbia. Natalie Henrich The evolutionary psychology of group cooperation.. Do people solve commons problems, and if so how? Field work among Chaldean communities in Detroit. PhD 2001. MpH from Harvard School of Public Health 2004.

Michelle Kline

Evolution of technology. The psychology of social learning of technical skills. The role of teaching in cultural transmission. Field work in Fiji. Stephen Le Friendship, cooperation, prisoner’s dilemma, evolutionary game theory. Fieldwork in Viet Nam. Now a Postdoctoral researcher, University of Hokkaido Sarah Mathew Evolution of cooperation; intergroup aggression and warfare in the context of cooperation in large groups; cultural evolution. Field work in N. Kenya. Currently postdoctoral researcher at the University of Stockholm. Starting Fall 2012, Assistant Professor, Dept. of Anthropology, SUNY Stony Brook NY Cristina Moya Social group categorization. Coalitional and ethnic psychology. Field work in highland Peru. Currently postdoctoral researcher London School of Hygiene & Tropical Medicine Population Studies Dept. Karthik Panchanathan Indirect reciprocity. Does selection favor doing good to those who do good. Experiments on reputation and cooperation. Currently teaching at Pomona College. Assistant Professor, Department of Anthropology, University of Missouri Jocelyn Peccei The evolution of menopause. Is menopause and adaptation, and if so why? Has estimated the heritability of age of menopause and the genetic covariation of ages of menopause and menarche. PhD 1999.Aimee Plourde Evolution of prestige economies. Why do people invest more resources in showy displays of wealth as political systems become more complex? Archaeological field work in Lake Titicaca region of Peru. Currently: Lecturer at the University of Bristol. Adam Wetsman The evolutionary psychology of mate choice. Do men modulate their preferences according to their own mate value, and why do men care so much about physical attractiveness? Has done extensive survey work with UCLA undergraduates. PhD 1999: Professor Rio Hondo College


Ph.D. Ecology, University of California Davis (1975)