Andrew W. Delton
Department of Psychological and Brain Sciences
University of California
Santa Barbara, CA 93106-9660
Research FocusMy research focuses on mapping the psychological mechanisms that allow humans to value others, to be generous, and to cooperate. I combine approaches from social, cognitive, and evolutionary psychology. I use a variety of methods, including laboratory experiments, socio-cognitive measures, behavioral economics, mathematical and computational modeling, neuropsychological patient studies, functional neuroimaging (fMRI), and cross-cultural data collection.
2010 - Present
Center for Evolutionary Psychology
Department of Psychological and Brain Sciences
University of California, Santa Barbara
Advisors: Leda Cosmides & John Tooby
Ph.D. Psychology, University of California, Santa Barbara, 2010
Area: Evolutionary psychology, specializing in social cognition and cooperation
Doctoral emphases earned based on advanced training and coursework:
Emphasis in Quantitative Methods for the Social Sciences
Emphasis in Cognitive Sciences
Emphasis in Interdisciplinary Human Development
M.A. Psychology, University of California, Santa Barbara, 2006
B.S. Psychology, Arizona State University, 2003
Summa cum laude
Graduate of Barrett Honors College
Cooperation and Generosity
Judgment and Decision Making
Concepts for cooperation
One line of my research explores the concepts that enable collective action and coalitional cooperation. The two concepts I have investigated most closely are the free rider concept and the newcomer concept. Free riders are individuals with an exploitative disposition to take collective benefits while not contributing. Newcomers are new members of a coalition who pose similar, but not identical, adaptive problems as free riders. My work has focused on critical hypothesis testing: determining whether these concepts are specialized for free rider and newcomer content per se, or are the products of more general mechanisms. A conference paper on this topic recently received the Human Behavior & Evolution Society’s Postdoctoral Researcher Award.
Delton, A. W., Nemirow, J., Robertson, T. E., Cimino, A., & Cosmides, L. (in press). Merely opting out of a public good elicits moralization: An error management approach to cooperation. Journal of Personality and Social Psychology.
Delton, A. W., Cosmides, L., Robertson, T. E., Guemo, M., & Tooby, J. (2012). The psychosemantics of free riding: Dissecting the architecture of a moral concept. Journal of Personality and Social Psychology, 102, 1252-1270. (pdf, Supplemental)
Delton, A. W. & Cimino, A. (2010). Exploring the newcomer concept: Experimental tests of a cognitive model. Evolutionary Psychology, 8, 317-335. (pdf)
Cimino, A. & Delton, A. W. (2010). On the perception of newcomers: Toward an evolved psychology of intergenerational coalitions. Human Nature, 21, 186-202. (pdf)
Petersen, M. B., Delton, A. W., Robertson, T. E., Tooby, J. and Cosmides, L. (2008). Politics in the evolved mind: Political parties and coalitional reasoning. Published conference proceedings of the Midwest Political Science Association 66th Annual National Conference, Chicago, IL.
The origins of generosity
A second line of research use computational methods to examine the evolution of generosity. Research often reveals that people cooperate and are generous even in anonymous, ephemeral interactions. Because this behavior appears to contradict many extant theories of cooperation, a variety of complicated models have been advanced to explain how it evolves. My work, however, shows that the contradiction is illusory and that simple mechanisms of direct reciprocity can select for agents willing to cooperate in one-shot encounters. Past work has previously neglected psychological considerations, such as the inherent uncertainty involved in real-world decision making. My work shows that generosity in ephemeral encounters evolves as a by-product of imperfect information: Because it is always uncertain whether a reciprocation partner will or will not be encountered again, it is best to treat everyone generously even if an interaction appears ephemeral. A conference paper on this topic, jointly authored with Max Krasnowreceived the Human Behavior & Evolution Society’s New Investigator Award.
*Krasnow, M.M., *Delton, A.W., Tooby, J. & Cosmides, L. (2013) Meeting now suggests we will meet again: Implications for debates on the evolution of cooperation. Nature Scientific Reports, 3, 1747; DOI:10.1038/srep01747. (pdf)
* indicates joint first authorship
Krasnow, M. M. & Delton, A. W. (2012). Is there evidence for special design of a group-selected psychology? Comment on Steven Pinker's The false allure of group selection. Edge. Retrieved from http://edge.org/conversation/the-false-allure-of-group-selection#mkad
Delton, A. W., Krasnow, M. M., Cosmides, L., & Tooby, J. (2011). Reply to McNally and Tanner: Generosity evolves when cooperative decisions must be made under uncertainty. Proceedings of the National Academy of Sciences of the United States of America, 108, E972. (pdf)
Delton, A. W., Krasnow, M. M., Cosmides, L., & Tooby, J. (2011). The evolution of direct reciprocity under uncertainty can explain human generosity in one-shot encounters. Proceedings of the National Academy of Sciences of the United States of America, 108, 13335-13340. (pdf)
Delton, A. W., Krasnow, M. M., Cosmides, L., & Tooby, J. (2010). Evolution of fairness: Rereading the data. Science, 329 (5990), 389. (pdf)
Welfare tradeoffs and social decision making
Another line of research explores the variables that underlie generosity, reciprocity and other social behaviors. My work is primarily focused on understanding how the mind makes welfare tradeoffs. This was the focus of my dissertation and is the focus of much ongoing work, including cross-cultural research, work with psychopaths, and neuroimaging. Additionally, I have worked on a series of collaborations that investigate how developmental and situational factors calibrate variables of risk and time preference.
Griskevicius, V., Ackerman, J. M., Cantú, S., Delton, A. W., Robertson, T. E., Simpson, J. A., Emery Thompson, M., & Tybur, J. M. (2013). When the economy falters, do people spend or save? Responses to resource scarcity depend on childhood environments. Psychological Science, 24, 197-205. (pdf)
Delton, A. W. & Robertson, T. E. (2012). The social cognition of social foraging: Partner selection by underlying valuation. Evolution and Human Behavior, 33, 715-725. (pdf)
*Sznycer, D., *Takemura, K., *Delton, A. W., Sato, K., Robertson, T. E., Tooby, J. (2012) Cross-cultural differences and similarities in proneness to shame: An adaptationist and ecological approach. Evolutionary Psychology, 10, 352-370. (pdf)
* indicates joint first authorship among DS, KT, and AWD
Griskevicius, V., Tybur, J. M., Ackerman, J. M., Delton, A. W., Robertson, T. E., & White, A. E. (2012). The financial conequences of too many men: Sex ratio effects on saving, borrowing, and spending. Journal of Personality and Social Psychology, 102 (1), 69-80. doi: 10.1037/a0024761. (pdf)
Griskevicius, V., Tybur, J. M., Delton, A. W., & Robertson, T. E. (2011). The influence of mortality and socioeconomic status on preferences for risk and delayed rewards: A life history theory approach. Journal of Personality and Social Psychology, 100, 1015-1026. (pdf)
Griskevicius, V., Delton, A. W., Robertson, & T. E., Tybur, J. M. (2011). Environmental contingency in life-history strategies: Influence of mortality and socioeconomic status on reproductive timing. Journal of Personality and Social Psychology, 100, 241-254. (pdf)
Delton, A. W. (2010). A psychological calculus for welfare tradeoffs. Unpublished dissertation, University of California, Santa Barbara.
Evolution and Memory
An additional line of research examines the adaptive design of memory. Although memory allows us to recall the past, a primary function is to regulate current and future behavior. A focus of this research has been on the future-orientation of memory and its role in planning.
Klein , S. B., Robertson, T. E., Delton, A. W., Lax, M. L. (2012). Familiarity and personal experience as mediators of recall when planning for future contingencies. Journal of Experimental Psychology: Learning, Memory, and Cognition, 38, 240-245. (pdf)
Klein, S. B., Robertson, T. E., & Delton, A. W. (2011). The future-orientation of memory: Planning as a key component mediating the high levels of recall found with survival processing. Memory, 19, 121-139. (pdf)
Klein, S. B., Robertson, T. E., & Delton, A. W. (2010). Facing the future: Memory as an evolved system for planning future acts. Memory and Cognition, 38, 13-22. (pdf)
Evolution and Social Cognition
I have also participated in collaborations to understand other aspects of social cognition, including adaptive disjunctions in the processing stream and the early-stage cognition of mate selection.
Kenrick, D. T., Delton, A. W., Robertson, T. E., Becker, D. V., & Neuberg, S. L. (2007). How the mind warps. In J. P. Forgas, M. G. Haselton, & W. Von Hippel (Eds.), The evolution of the social mind: Evolutionary psychology and social cognition (pp. 49-68). New York: Psychology Press. (pdf)
Delton, A. W., Robertson, T. E., & Kenrick, D. T. (2006). The mating game isn’t over: A reply to Buller’s critique of the evolutionary psychology of mating. Evolutionary Psychology, 4, 262-273. (pdf)
Maner, J. K., Kenrick, D. T., Becker, D. V., Robertson, T. E., Hofer, B., Neuberg, S. L., Delton, A. W., Butner, J., & Schaller, M. (2005). Functional projection: How fundamental social motives can bias interpersonal perception. Journal of Personality and Social Psychology, 88, 63-78. (pdf)
Maner, J. K., Kenrick, D. T., Becker, D. V., Delton, A. W., Hofer, B., Wilbur, C. J., & Neuberg, S. L. (2003). Sexually selective cognition: Beauty captures the mind of the beholder. Journal of Personality and Social Psychology, 85, 1107-1120. (pdf)