تکامل و نوع دوستی: ترکیب واسطه ای با تمایلات روانی به طور طبیعی انتخاب شده

This study integrates psychological predictors of helping intentions and naturally selected tendencies enhancing inclusive fitness for a more comprehensive understanding of altruism. Psychological mediators of helping intentions, empathic concern and oneness, and psychological processes facilitating kin selection and reciprocal altruism were combined in a structural equation model to predict participants' (N=643) intentions to perform a risky rescue behavior. The tendency for reciprocal altruism and kinship were the strongest predictors of rescue intentions. Confirming previous research, empathic concern made a significant but small contribution in predicting helping intentions. Proximate mechanisms currently in the psychological literature did not entirely account for the effect of kinship on helping intentions.

1.1. Psychological altruism and egoism Research on altruism attempts to illuminate fundamental characteristics of human nature. Batson et al.'s (1997) empathy–altruism hypothesis proposes that empathic concern evokes an altruistic motivation. Studies supporting this hypothesis have systematically varied whether individuals can only obtain egoistic goals by helping, or whether they can escape from the situation and obtain the egoistic goals without helping (Batson & Shaw, 1991). These studies purportedly demonstrate that at least some people have helping intentions that are not explained by egoistic motivations, such as the relief of personal distress (Batson & Shaw, 1991), escaping public shame for not helping (Batson & Shaw, 1991), the relief of sadness (Batson et al., 1989), and the desire to make oneself happy (Batson et al., 1991). Cialdini, Brown, Lewis, Luce, and Neuberg (1997) have proposed that it is the sense of self–other overlap, or “oneness” between the helper and the individual in need, that motivates helping, rather than empathy. Helping others with whom one feels commonality would not be selfless, because it leads to a more favorable mental state. Studies examining whether the effect of empathic concern can be eliminated when the sense of oneness with the target, or “self–other overlap,” is accounted for have produced contradictory results Batson et al., 1997 and Cialdini et al., 1997. 1.2. Integrating proximate and ultimate influences Although some claim that no clear evidence exists for the operation of inclusive fitness enhancing processes in humans (e.g., Batson, 1997), specific predictions based upon kin selection have empirical support (e.g., Essock-Vitale & McGuire, 1985). In a series of experiments, Burnstein, Crandall, and Kitayama (1997) demonstrated how the consequences to evolutionary fitness influenced target selection in life or death rescue scenarios and everyday helping behaviors. Shavit, Fischer, and Koresh (1994) have provided data revealing nepotistic actions in real-life emergency situations. Altruism advocates define altruism as “a motivational state with the ultimate goal of increasing another's welfare” (Batson, 1991 p. 6). The distinction between self and other is confounded when one considers benefits at the genetic level. Altruist advocates admit that evolutionary theorists have been useful in revealing how self-sacrificial behavior can be consistent with the theory of natural selection, however, they are more concerned with the driving mental motivation of the helper (Batson, 1991). Consistent with evolutionary theory, the experience of oneness or empathy could arise as a consequence of attachment-related cues (kinship, friendship, familiarity) that signaled the potential for relatively high genetic commonality in the EEA (Kenrick, 1991). The psychological states provoked by these cues could increase the chances of the needy individuals receiving assistance, enhancing the survival and replication of genes influencing the psychological capacities for oneness and empathy. This would account for the altruism advocates' example of a mother rushing to help her injured child (Kenrick, 1991). Genes promoting their own self-propagation may operate through actions that could be considered psychologically altruistic. Empirical hypotheses for helping intentions can be generated from the integration of psychological and evolutionary theory. Hypothesis 1. Kinship should have a significant positive impact on the mental states (oneness and empathic concern) that serve as proximate mediators of helping intentions. Hypothesis 2. Kinship should also make a significant unique contribution to the variance explained in helping intentions. People do not need to be aware of the inclusive fitness consequences of their actions for tendencies to be naturally selected. Nonconscious processes may also be quicker than conscious processes, an advantage in critical situations where survival is determined in a matter of seconds. Hypothesis 3. Following from reciprocal altruism theory, it is predicted that an individual's helping intentions will reflect the expected likelihood for the target to help if positions in the situation were reversed. Hypothesis 4. Participants should have a higher expected likelihood for kin helping them than for nonkin helping them, an intuitive expression of inclusive fitness theory.