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The evolution of cooperation is an unsolved research topic and has been investigated from the viewpoint of not only biology and other natural sciences but also social sciences. Much extant research has focused on the evolution of cooperation among peers. While, different players belonging to different organizations play different social roles, and players playing different social roles cooperate together to achieve their goals. We focus on the evolution of cooperation in linear division of labor that is defined as follows: a player in the i-th role interacts with a player in the i + 1-th role, and a player in the n-th role achieves their goal (1 <= i < n) if there are n roles in the division of labor. We take the industrial waste treatment process as an example for illustration. We consider three organizational roles and B-i is the i-th role. The player of B; can choose two strategies: legal treatment or illegal dumping, which can be interpreted as cooperation or defection (i = 1-3). With legally required treatment, the player of B-j pays a cost to ask the player of Bj+1 to treat the waste (j = 1, 2). Then, the cooperator of Bj+1 pays a cost to treat the waste properly. With illegal dumping, the player of Bi dumps the waste and does not pay any cost (i= 1-3). However, the waste dumped by the defector has negative environmental consequences, which all players in all roles suffer from. This situation is equivalent to a social dilemma encountered in common-pool resource management contexts. The administrative organ in Japan introduces two sanction systems to address the illegal dumping problem: the actor responsibility system and the producer responsibility system. In the actor responsibility system, if players in any role who choose defection are monitored and discovered, they are penalized via a fine. However, it is difficult to monitor and detect the violators, and this system does not work well. While, in the producer responsibility system, the player in B-1

A field study was conducted to investigate the reduction of plastic bag usage at supermarkets. Many behaviors leading to potential damage to the environment may be unintentional. This study applied a dual motivation model to plastic bag usage and examined the effects of an intervention aimed at promoting pro-environmental behavior. A voice prompt intervention was implemented in Japanese supermarkets. In the first (control) week, shoppers were given free plastic bags by the cashier. In the second (intervention) week, cashiers asked shoppers whether they wanted plastic bags. We collected observational and questionnaire measures of variables that predicted free plastic bag usage during the intervention. The results supported a dual motivation model of behavioral change. The voice prompt decreased the usage of plastic bags by both discouraging unintentional usage and encouraging an intentional reduction in usage. Possibilities for interventions designed both to attenuate unintentional motivation and to promote intentional motivation are considered.