title: Are social norms and reciprocity necessary for early helping?
authors.affiliation: Department of Psychology, Harvard University, Cambridge, MA 02138 warneken@wjh.harvard.edu.
authors.forename: Felix
authors.initials: F
authors.lastname: Warneken
mesh_terms: D000533:Altruism; D026686:Beneficence; D003463:Cues; D005260:Female; D006801:Humans; D008297:Male; D012919:Social Behavior