Evolutionary Theory Oxford Handbooks Online Evolutionary Theory John H. Shaver, Grant Purzycki, and Richard Sosis The Oxford Handbook of the Study of Religion Edited by Michael Stausberg and Steven Engler Print Publication Date: Nov 2016 Subject: Religion, Religion and Science Online Publication Date: Jun 2017 DOI: 10.1093/oxfordhb/9780198729570.013.9 Abstract and Keywords People in all cultures entertain beliefs in supernatural agents and engage in ritual behaviors that are related to those beliefs. This suggests that religion is a product of a shared evolutionary history. Currently researchers employ three major evolutionary frameworks to study religion—evolutionary psychology, behavioral ecology, and dual- inheritance theory—each with different assumptions, methods, and areas of focus. This chapter surveys these approaches and describes the major sources of disagreement between them. Two of the largest sources of disagreement among evolutionary scholars of religion are: (1) whether or not religion is a cognitive byproduct, or a manifestation of adaptive behavioral plasticity, and (2) whether or not individual or group-level selection processes are a more potent evolutionary force in shaping the significant features religion. The authors suggest that integrative frameworks that incorporate aspects of all these perspectives offer the best potential for real progress. Keywords: behavioral ecology, dual-inheritance theories of religion, evolutionary psychology of religion, evolutionary theory of religion, group selection, religion as by-product Chapter Summary • People in all cultures engage in ritual behaviors and hold beliefs in supernatural agents. This universality suggests that religion is a product of a shared evolutionary history. • Although there has been a recent surge in the evolutionary study of religion, this has not been a unified endeavor. 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Subscriber: OUP-Reference Gratis Access; date: 12 June 2017 Evolutionary Theory • Currently researchers employ three major evolutionary frameworks to study religion —evolutionary psychology, behavioral ecology, and dual inheritance theory—each with different assumptions, methods, and areas of focus. • Two of the largest sources of disagreement between evolutionary scholars of religion are: (1) religion as cognitive by-product vs. manifestation of adaptive behavioral plasticity; and (2) individual- vs. group-level selection processes as forces shaping religion. • Integrative frameworks that incorporate aspects of all perspectives offer the best potential for real progress. The Evolutionary Science of Religion Evolutionary theorists generally view religion as ritual behavior that is motivated and/or rationalized by appeals to supernatural agents (e.g. Purzycki/Sosis 2013).1 Both rituals (p. 125) and supernatural beliefs exist in nearly all known human societies, and across cultures religions are structurally quite similar (Boyer 2001; Bulbulia 2005; Rappaport 1999). The universality and shared structure of religions beg evolutionary investigation. It is thus perhaps unsurprising that evolutionary approaches to the study of religion have flourished in recent years, as part of a general rise of evolutionary thinking across the sciences, and continue to inspire considerable empirical work. However, efforts to apply Darwinian theory to the study of religion do not represent a single unified endeavor or research program. The focus of study is often a critical factor in determining how researchers interpret the effects of natural selection on religion. When, for instance, researchers concentrate on the cognitive requirements of religious thought, they typically conclude that religious beliefs are merely by-products of psychological adaptations designed for other purposes (e.g. Boyer 2001; Guthrie 1993). On the other hand, when researchers examine the social consequences of ritual behavior, the adaptive benefits of religion become quite clear (e.g. Alcorta/Sosis 2005). And when research emphasizes individual variation in religious behavior, it is obvious that these adaptive benefits are not equally achieved; some benefit more than others (e.g. Cronk 1994). However, research focused on group-level dynamics reveals that some religious groups are more successful than others, and this may be, in part, because they are better able to minimize individual self-interested behaviors and instead motivate behaviors that result in benefits for the group. Scholars pursuing such research argue that religious groups function as adaptive units that are subject to cultural group selection (e.g. Norenzayan 2013; Wilson 2002). These differences in research foci roughly correspond to three relatively distinct evolutionary approaches to the study of human behavior: evolutionary psychology, human behavioral ecology, and dual inheritance theory (Smith 2000). Here we describe how each Page 2 of 16 PRINTED FROM OXFORD HANDBOOKS ONLINE (www.oxfordhandbooks.com). (c) Oxford University Press, 2015. All Rights Reserved. Under the terms of the licence agreement, an individual user may print out a PDF of a single chapter of a title in Oxford Handbooks Online for personal use (for details see Privacy Policy). Subscriber: OUP-Reference Gratis Access; date: 12 June 2017 Evolutionary Theory of these evolutionary subfields has approached the study of religion. We then suggest that viewing these approaches as complementary, rather than contradictory, offers the greatest potential to explain the complex phenomenon of religion (Sosis 2009; Sosis/ Bulbulia 2011). Since evolved cognitive faculties, memory and its organization, behavioral expression, interpersonal social psychological responses, and the social and natural environments are all at play in the formation of religious systems, diverse approaches are necessary if we wish to uncover the evolutionary origins and development of religion. Evolutionary Psychology of Religion Evolutionary psychologists use the theory of natural selection to generate hypotheses about panhuman psychological design; they contend that the human mind consists of (p. 126) several cognitive systems designed to solve specific adaptive problems that ancestral human populations faced (Tooby/Cosmides 1992; cf. Barrett et al. 2014; Samuels 1998). Because the human brain consists of cognitive adaptations to solve ancestral problems, and because modern environments often differ substantially, cognitive adaptations can produce thoughts and behaviors that are now neutral, maladaptive, or even unrelated to the problems they arose to solve. Indeed, the majority of evolutionary psychologists of religion hold that the human tendency for supernatural beliefs is an evolutionary by-product of cognitive systems that evolved to solve adaptive problems unrelated to religion (Bulbulia 2004; Sosis 2009). That is, the human proclivity for belief in the supernatural is the result of an evolved panhuman psychological design, but the cognitive architecture that supports supernatural belief did not arise because believing in supernatural agents itself was adaptive. The research questions evolutionary psychologists address include the developmental trajectories of the cognitive abilities assumed to contribute to supernatural belief, their presence in adults, and their cross- cultural prevalence, and they generally test their assumptions with laboratory experiments and/or survey research. Evolutionary psychologists of religion assume that several cognitive systems contribute to our propensity for belief in the supernatural. Notably, Guthrie (1993) argues that the human tendency to anthropomorphize arose as a result of selection pressures that favored the ability to perceive agents and agency in the environment and that these abilities contribute the human propensity to interpret events in terms of supernatural agency. He suggests that perceiving agents, even when there are none, is advantageous insofar as not detecting agents that are present would be deleterious (e.g. not detecting a nearby mountain lion). While this promiscuous agency detection did not emerge for purposes relating to religion, and the evolutionary roots of this capacity run quite deep, it is nonetheless the ability to perceive unseen agents that gives rise to religious perceptions and explanations of the mysterious (Barrett 2004). Furthermore, myths, spirits, and god perceptions are the natural by-product of such a sensitive system; we Page 3 of 16 PRINTED FROM OXFORD HANDBOOKS ONLINE (www.oxfordhandbooks.com). (c) Oxford University Press, 2015. All Rights Reserved. Under the terms of the licence agreement, an individual user may print out a PDF of a single chapter of a title in Oxford Handbooks Online for personal use (for details see Privacy Policy). Subscriber: OUP-Reference Gratis Access; date: 12 June 2017 Evolutionary Theory explain the world in terms of agency, and frequently believe that events are caused by supernatural agents. Human social interactions require the ability to understand and appreciate what others are thinking and feeling. Indeed, human sociality is built on the cognitive ability to interpret other individuals as having their own distinct perceptions, desires, and beliefs. This capacity, known as theory of