title: Transition from reciprocal cooperation to persistent behaviour in social dilemmas at the end of adolescence.
abstract: While human societies are extraordinarily cooperative in comparison with other social species, the question of why we cooperate with unrelated individuals remains open. Here we report results of a lab-in-the-field experiment with people of different ages in a social dilemma. We find that the average amount of cooperativeness is independent of age except for the elderly, who cooperate more, and a behavioural transition from reciprocal, but more volatile behaviour to more persistent actions towards the end of adolescence. Although all ages react to the cooperation received in the previous round, young teenagers mostly respond to what they see in their neighbourhood regardless of their previous actions. Decisions then become more predictable through midlife, when the act of cooperating or not is more likely to be repeated. Our results show that mechanisms such as reciprocity, which is based on reacting to previous actions, may promote cooperation in general, but its influence can be hindered by the fluctuating behaviour in the case of children.
authors.affiliation: Departament de Física Fonamental, Universitat de Barcelona, Martí i Franqués 1, Barcelona 08028, Spain.
authors.forename: Mario
authors.initials: M
authors.lastname: Gutiérrez-Roig
authors.affiliation: Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, Zaragoza 50018, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Gracia-Lázaro
authors.affiliation: Departament de Física Fonamental, Universitat de Barcelona, Martí i Franqués 1, Barcelona 08028, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Perelló
authors.affiliation: 1] Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, Zaragoza 50018, Spain [2] Departamento de Física Teórica, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza 50009, Spain [3] Complex Networks and Systems Lagrange Lab, Institute for Scientific Interchange, Turin 10126, Italy.
authors.forename: Yamir
authors.initials: Y
authors.lastname: Moreno
authors.affiliation: 1] Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, Zaragoza 50018, Spain [2] Grupo Interdisciplinar de Sistemas Complejos (GISC), Departamento de Matemáticas, Universidad Carlos III de Madrid, Avenida de la Universidad 30, Leganés, Madrid 28911, Spain.
authors.forename: Angel
authors.initials: A
authors.lastname: Sánchez
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D003299:Cooperative Behavior; D005260:Female; D005716:Game Theory; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D008875:Middle Aged; D012919:Social Behavior; D055815:Young Adult