STUDY: Monkeys don't like humans who are mean to other humans

A new study, published in Nature Communications, explains that monkeys are skeptical of humans who are mean to other humans. In Third-party social evaluation of humans by monkeys, James R. Anderson, Hika Kuroshima, Ayaka Takimoto, and Kazuo Fujita outline their findings, positing that tufted capuchin monkeys were less likely to trust humans who were observed being less than helpful to other humans.

We find that the monkeys accept food less frequently from those who persistently reject another's requests for help. This negative social evaluation effect is robust across conditions, and tightly linked to explicit refusal to help. Evaluation of potential helpfulness based on third-party interactions may thus not be unique to humans. [Nature Communications]