New! When cooperation is organized as a public good even people who do not contribute can still access the benefits that cooperation creates. How does the structure of public goods affect moral reactions to people who merely opt out of cooperation – even if they do not take the benefits of cooperation?
To find out, see Merely opting out of a public good is moralized: An error management approach to cooperation. by Andrew Delton, Jason Nemirow, Theresa Robertson, Aldo Cimino, and Leda Cosmides in the Journal of Personality and Social Psychology (DOI: 10.1037/a0033495).
New! Do humans view issues of economic redistribution through the lens of cognitive adaptations for contests over resources? To find out, see The ancestral logic of politics: Upper-body strength regulates men’s assertion of self-interest over economic redistribution. by Michael Bang Petersen, Daniel Sznycer, Aaron Sell, Leda Cosmides, and John Tooby in Psychological Science (DOI: 10.1177/0956797612466415).
New! Natural selection builds brains and bodies to mesh with the structure of ancestral environments. What implications does this have for debates on the evolution of cooperation? To find out, see Meeting now suggests we will meet again: Implications for debates on the evolution of cooperation by Max Krasnow, Andrew Delton, John Tooby, and Leda Cosmides in Nature Scientific Reports (DOI:10.1038/srep01747).
New! Will the second wave of the cognitive revolution tackle motivation? To find out, see Evolutionary psychology: New perspectives on cognition and motivation by Leda Cosmides and John Tooby in Annual Review of Psychology, 64, 201-229.
New! What explains the origins of personality trait covariation? To find out, see Testing an Adaptationist Theory of Trait Covariation: Relative Bargaining Power as a Common Calibrator of an Interpersonal Syndrome, by Aaron W. Lukaszewski in the Eurpoean Journal of Personality (DOI: 10.1002/per.1908).
New! What are relationship representations for? We report new developmental data on one of the core functions of coalitional psychology: using relationship information to make predictions about others. See Coalitional psychology on the playground: Reasoning about indirect social consequences in preschoolers and adults by David Pietraszewski and Tamsin C. German in Cognition, March 2013, 126(3), 352-363.
Humans share food and other resources with each other in biologically unprecedented ways. What are some of the psychological abilities that make this possible? See The social cognition of social foraging: Partner selection by underlying valuation by Andrew Delton & Theresa Robertson
What explains our strong inclination to track the reputations of others and to punish their bad behavior? We report new empirical tests that suggest these features of human nature are adaptations for deriving benefits from small-scale interactions, not from inter-group competition. See What are punishment & reputation for? by Max Krasnow, Leda Cosmides, Eric Pedersen, & John Tooby in PLOS ONE, 2012. (UCSB Press Release; Supplemental)
Are there specialized psychological mechanisms that allow humans to cooperate in groups? In a recent series of studies, we have explored whether the mind has an evolved concept for identifying free riders, individuals who take the benefits of group cooperation without contributing. Delton, A. W., Cosmides, L., Guemo, M., Robertson, T. E., & Tooby, J. (2012). See The psychosemantics of free riding: Dissecting the architecture of a moral concept. Journal of Personality and Social Psychology. Advance online publication. (Supplemental)
What explains why humans are so generous, even in one-shot interactions? We show how the inherent uncertainty of social decision making, in combination with selection for direct reciprocity, leads to striking amounts of generosity. Our work reveals that natural selection creates motivation to be generous even in situations where generosity appears economically irrational. See The evolution of direct reciprocity under uncertainty can explain human generosity in one-shot encounters by Andrew W. Delton, Max M. Krasnow, Leda Cosmides & John Tooby in Proceedings of the National Academy of Sciences, 2011. Click here for more
Click here to see our reply to a recent commentary on our article.
Click here to see a Science letter by Delton, Krasnow, Cosmides, & Tooby on alternative approaches to the evolution of cooperation.
What explains the origins of individual differences in personality? Does adaptively-patterned personality variation arise via specific gene polymorphisms (as predicted by evolutionary genetic models) or universal mechanisms of facultative calibration (as predicted by adaptationist models)? See The origins of extraversion: Joint effects of facultative calibration and genetic polymorphism by Aaron W. Lukaszewski and James R. Roney in Personality and Social Psychology Bulletin, March 2011, 37(3) 409–421.
Cross-cultural evidence for a domain specific adaptation in human spatial cognition for plant food gathering. See Cognitive adaptations for gathering-related navigation in humans by Max Krasnow, Danielle Truxaw, Steven Gaulin, Joshua New, Hiroki Ozono, Shota Uono, Taiji Ueno, and Kazusa Minemoto in Evolution and Human Behavior, January 2011 32 (2011) 1–12.
Does the human mind contain adaptations for integrating newcomers into coalitions? See On the perception of newcomers: Toward an evolved psychology of intergeneration coalitions by Aldo Cimino and Andrew Delton in Human Nature (21:186–202)and Exploring the evolved concept of newcomer: Experimental tests of a cognitive model by Andrew Delton and Aldo Cimino in Evolutionary Psychology 8(2): 317-335.
Cross cultural research demonstrates that the male voice contains cues of fighting ability and upper body strength. See Adaptations in humans for assessing physical strength from the voice by Aaron Sell, Gregory Bryant, Leda Cosmides, John Tooby, Daniel Sznycer, Christopher von Rueden, Andre Krauss and Michael Gurven in Proceedings of the Royal Society London, (Biological Sciences), 277, 3509-3518.
Just how specialized is the cheater detection mechanism? New research shows that it is activated only when the search for rule violations has the potential to reveal someone’s character—their propensity to cheat. It does not search for violations of social exchange rules when these are accidental, when they do not benefit the violator, or when the situation would make cheating difficult. See Adaptive specializations, social exchange, and the evolution of human intelligence by Cosmides, L., Barrett, C., & Tooby, J. in Proceedings of the National Academy of Sciences, 107, 9007-9014, May 2010, . click here for more
Why does anger exist, what is its evolved function, and why are some people more anger prone than others? See Formidability and the logic of human anger by Aaron Sell, Leda Cosmides, and John Tooby, in Proceedings of the National Academy of Sciences, 106(35) 15073–15078, September 2009. Click here for more
Theories of animal conflict predict that humans should have an evolved specialization for assessing fighting ability. See Human adaptations for the visual assessment of strength and fighting ability from the body and face by Aaron Sell, Leda Cosmides, John Tooby, Daniel Sznycer, Christopher von Rueden, and Michael Gurven in Proceedings of the Royal Society London, (Biological Sciences), 276, 575–584. October 2008. Click here for more
Does the presence of status rivals affect risky decision-making in men? Are motivation and cognition inextricably bound together? See Relative Status Regulates Risky Decision-Making about Resources in Men: Evidence for the Co-Evolution of Motivation and Cognition by Elsa Ermer, Leda Cosmides, and John Tooby, in Evolution and Human Behavior, 29, 106-118 (2008).
Category-Specific Attention for Animals Reflects Ancestral Priorities, not Expertise” by Joshua New, Leda Cosmides, and John Tooby. In the October 16, 2007 Proceedings of the National Academy of Sciences, Vol. 104, 16598-16603. Click here for discussion
Spatial Adaptations for Plant Foraging: Women Excel and Calories Count by Joshua New, Max Krasnow, Danielle Truxaw, and Steven J.C. Gaulin. In Proceedings of the Royal Society, Biological Sciences 274, 2679-2684 (2007). Click here for more, including Krasnow, Truxaw, New & Gaulin's response to Brumfield et al. in Science...
Does reasoning about social exchange engage different brain areas than other kinds of reasoning? To find out, see:
Ermer, E., Guerin, S., Cosmides, L., Tooby, J., & Miller, M. (2006) Theory of mind broad and narrow: Reasoning about social exchange engages ToM areas, precautionary reasoning does not. Social Neuroscience, 1 (3-4), 196-219.
Is it possible to prevent people from automatically categorizing others by race? Years of psychological research suggest that race is always encoded in the process of impression formation, but the idea that the mind would have evolved mechanisms to identify racial categories is implausible given that our hunter-gatherer ancestors rarely to never encountered people of different races. See Can race be erased?: Coalitional computation and social categorization by Robert Kurzban, John Tooby, and Leda Cosmides in Proceedings of the National Academy of Sciences, 98(26), 15387-15392. Click here for more
The Architecture of Human Kin Detection by Debra Lieberman, John Tooby, & Leda Cosmides. Nature, 445, 727-731 (Feb 15, 2007). Click here for more
The Center for Evolutionary Psychology has a sister center in Japan, the Center for the Sociality of Mind, at Hokkaido University.
Interview with Leda Cosmides (El Mercurio, October 28, 2001) Click here
Interview with Leda Cosmides (Psychology Today, August 12, 2013) Click here