Evolutionary Psychology Sample Research Proposal

Glenn Geher; Evolutionary Psychology (PSY 307)


Cosmides and Tooby (1992) have found that people are particularly good at detecting cheaters – and they have this idea rooted in Trivers’ (1971) theory of reciprocal altruism, which suggests that people help non-kin with an unconscious expectation of being helped in return.

In their research on this topic, Cosmides and Tooby (1992) use the Wason Selection task, a logic task that can be modified for different purposes. They found that people are better at getting the logical answer correct in this task if the task is presented in terms of detecting cheaters. For instance, people are better able to get the correct answers on this task if it is framed in terms of whether someone fails to bring firewood to a hut, even though the agreement among the people in his or her group is that everyone who stays there has to do it. People do very well when the task is framed this way – they tend to do poorly when the task is not framed in a way that relates to detecting cheaters.

The current research is interested in whether people are better at detecting cheaters on social contracts in real-life situations compared with detecting people who cheat in non-social contexts. For instance, if we see someone who fails to pay back a debt to a friend, are we better at remembering the details of that compared with if we see someone who fails to clean his bathroom on a day that he or she promised him or herself. Here, one situation is clearly relevant to a social contract with another person; the other is not.


In terms of methods, two 20-minute videos will be made using the same actor. The videos will simply be about the actor planning a mundane day and then it will be a documentary of the person going through the motions. In the first case, the actor will say “I’m going to pay Joe that $10 I owe him today.” In the other, the actor will casually mention, “I’m going to clean the bathroom today.”

50 participants will see the “pay Joe” version of the movie; the other 50 will see the “clean bathroom” version. Then the movies will be identical from there, showing Joe going to the store, running various other errands, etc. Importantly, Joe will not repay the debt nor clean his bathroom in either version.

Participants will then be asked to write, in an open-ended manner, for 10 minutes, details that they recall from the movie.

A team of five judges will read the content written by the participants and simply determine if the issues of (a) “repaying Joe” or (b) “cleaning the bathroom” emerge.

Anticipated Results

The prediction is that people in the social-contract condition (i.e., the repaying Joe condition) will be more likely to mention the fact that the debt was not repaid compared with the other condition – in which we expect the fact that the bathroom was not cleaned to be mentioned less.


Such findings would substantiate Cosmides and Tooby’s (1992) claim that people’s minds are particularly astute when it comes to detecting individuals who cheat on social contracts – providing relatively ecologically valid data on this issue.


Cosmides, L. & Tooby, J. (1992) Cognitive adaptations for social exchange. In J. Barkow, L. Cosmides, & J. Tooby (Eds.), The adapted mind: Evolutionary psychology and the generation of culture. New York: Oxford University Press.

Trivers, R.L. (1972). Parental investment and sexual selection. In B. Campbell (Ed.), Sexual selection and the descent of man, 1871-1971 (pp. 136–179). Chicago, IL: Aldine