Abstract

Humans are not only universally prosocial (Tomasello, 2009) but also selective when engaging in prosocial behavior (Kuhlmeier, Dunfield, & O’Neill, 2014). Despite numerous observations of selective helping, the proximate mechanisms underlying this critical social behavior remain unclear. In a series of 3 studies, two possible evaluative mechanisms, global evaluations and dispositional evaluations, was examined, regarding how individuals identify and track good social partners. To test between these two possibilities, these studies varied the type of information participants had regarding an individual’s characteristics and examined how this information influenced participants’ partner choice decisions. The stimuli to be used in the latter two studies were normed (Study 1), and the items were finalized because these various descriptions across characteristics shared similar positive or negative valence. In Study 2, adults read descriptions of two characters varying on prosocial (Helpful and Generous), social (Prestigious and Considerate), or non-social (Attractive and Intelligent) characteristics. They were then asked to indicate who they preferred to help or interact with. Adults took both valence and specificity of characteristic described into account to make decisions, suggesting a flexible use of dispositional evaluations. Study 3 extended these findings by examining how 4-year-olds used similar characteristics to determine who to help, play with, and assign food to. Children appeared to engage in global evaluations - preferring to help, to play with, and to assign the preferred food to the positive characters regardless of specific characteristic described. Taken together, these results suggest that the evaluative mechanisms supporting selective prosociality change over development.