The ability to choose the partners we interact with is thought to have been an important driver in the evolution of human social behavior, and in particular, for our propensity to cooperate. But evidence for this claim comes largely from Western populations. Here, we investigate qualities associated with being a preferred partner (i.e. campmate) in Hadza hunter-gatherers of northern Tanzania. Ninety-two Hadza participants from 12 camps ranked their current campmates on character traits (i.e.

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... d work, generosity, and honesty), hunting ability in men, and their preference for them as future campmates. We found positive but weak associations between rankings on character traits and being a preferred campmate. However, there was suggestive evidence that being perceived as a better hunter was a more important criterion than any character traits for being a preferred campmate in men. And we found little evidence to suggest that partner preferences were reciprocated among campmates. Finally, we found little evidence to suggest that being a preferred campmate is associated with greater reproductive success, which suggests there is little benefit to being a valued partner. Together, these findings suggest that social selection for character traits was not a powerful driving force in the evolution of human cooperation.