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THE BIOLOGY OF RELIGIOUS BEHAVIOR, Edited by Jay R. Feierman

[pp. 184-186] DISPERSAL

Dispersal is important in biology. Many amazing biological devices have evolved to ensure it, such as the production of fruits and nectar by plants and the provision of tasty protuberances called elaiosomes by seeds to attract insects. Often a species will produce two forms:

(1) a maintenance phenotype (the outcome of genes and the structures they produce interacting with a specific environment) that is adapted to the environment in which it is born, and (2) a dispersal phenotype that is programmed to move to a new area and that often has the capacity to adapt to a new environment.40

According to the present theory, humans have developed two dispersal phenotypes in the forms of the prophet and the follower. The coordinated action of these two phenotypes would serve to disperse us over the available habitat. This dispersal must have been aided by the major climatic changes over the past few million years in which vast areas of potential human habitat have repeatedly become available because of melting of ice sheets.

The dispersal phenotypes might have evolved through selection at the individual level, since the reproductive advantage of colonizing a new habitat would have been enormous. They would also promote selection between groups. This is important because selection at the group level can achieve results not possible at the level of selection between individuals. One result of the dispersal phenotype includes ethnocentrism (the tendency to favor one's own ethnic group over another) and the tendency to use "ethnic cleansing." The other result, as previously noted, is selection for cooperation, self-sacrifice, and a devotion to group rather than individual goals. Factors that promote selection at the group level are rapid splitting of groups, small size of daughter groups, heterogeneity (differences) of culture between groups, and reduction in gene flow between groups. These factors are all promoted by the breaking away of prophet-led groups with new belief systems.

One of the problems of selection at the group level is that of free-riders. These are people who take more than their share and contribute to the common good of the group less than their proper share. Selection at the group level gives free-riders their free ride. They potentially could increase until they destroy the cooperative fabric of the group.

However, the psychology of the free-rider, which is one of self-aggrandizement and neglect of group goals, is not likely to be indoctrinated with the mazeway of the group. Nor is it likely to be converted to the new belief system of the prophet. Therefore, theoretically one would predict that cults and New Religious Movements should be relatively free of free-riders. Such an absence of free-riders would further enhance selection at the group level. Moreover, this is a testable theoretical proposition.

Cult followers have been studied and found to be high on schizotypal traits, such as abnormal experiences and beliefs.42 They have not yet been tested for the sort of selfish attitudes and behavior that char acterize free-riders. If a large cohort of people were tested for some measure of selfishness, it is predicted that those who subsequently joined cults would be low on such a measure. Predictions could also be made about future cult leaders. They would be likely to be ambitious males who were not at the top of the social hierarchy of their original group. If part of why human groups split in general is to give more reproductive opportunities to males in the new group, it can also be predicted that leaders of new religious movements would be males of reproductive age. Female cult leaders are not likely to be more fertile as a result of having many sexual partners, but their sons might be in an advantageous position for increased reproduction.

CONCLUSION

The biobehavioral science of ethology is about the movement of individuals. We have seen that change of belief system has been responsible for massive movements of individuals over the face of the earth. Religious belief systems appear to have manifest advantages both for the groups that espouse them and the individuals who share them. It is still controversial whether belief systems are adaptations or by-products of other evolutionary adaptive processes. Regardless of the answer to this question, the capacity for change of belief system, both that seen in the prophet and also that seen in the follower, may be adaptations because they have fostered the alternative life history strategies of dispersal from the natal habitat.

Moreover, change of belief system, when it is successful in the formation of a new social group and transfer of that group to a "promised land," accelerates many of the parameters that have been thought in the past to be too slow for significant selection at the group level, such as eliminating free-riders, rapid group splitting, heterogeneity between groups and reduction of gene transfer between groups. Natural selection at the group level would also favor the evolution of the capacity for change of belief system, so that during the past few million years we may have seen a positive feedback system leading to enhanced cult formation and accelerated splitting of groups. This may have contributed to the rapid development of language and culture in our lineage.

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