“…However, when and whom one can or will help highlight differences in individuals' ability to share and to compete for resources. The extent that people engage in acts of reciprocity also reflects their perceptions of whether they feel others have treated them fairly and whether those people are trustworthy (Koopman, Lin, Lennard, Matta, & Johnson, 2019;Marescaux, De Winne, & Rofcanin, 2019;Matta, Sabey, Scott, Lin, & Koopman, 2019). Those considerations make the human cognition of social comparison salient.…”