Humans are an ultrasocial species. This sociality, however, cannot be fully explained by the
canonical approaches found in evolutionary biology, psychology, or economics …

Extensive cooperation among unrelated individuals is unique to humans, who often sacrifice
personal benefits for the common good and work together to achieve what they are unable …

Online labor markets provide new opportunities for behavioral research, but conducting
economic experiments online raises important methodological challenges. This particularly …

Direct reciprocity is a powerful mechanism for the evolution of cooperation on the basis of
repeated interactions,,–. It requires that interacting individuals are sufficiently equal, such …

Highlights•Laypeople's beliefs about their country's income and wealth distributions are
typically inaccurate.•These misperceptions are caused in part by overreliance on cues from …

Sustaining large-scale public goods requires individuals to make environmentally friendly
decisions today to benefit future generations,,,,–. Recent research suggests that second …

Contemporary society is facing many social dilemmas—including climate change, COVID-
19, and misinformation—characterized by a conflict between short-term self-interest and …

Abstract Studies on Amazon Mechanical Turk (MTurk) often include check questions in
personality inventories to ensure data quality. However, a subset of MTurk workers may give …

Humans work together in groups to tackle shared problems and contribute to local club
goods that benefit other group members. Whereas benefits from club goods remain group …

People routinely cooperate with each other, even when cooperation is costly. To further
encourage such pro-social behaviors, recipients often respond by providing additional …