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The Substance of Cultural Evolution: Expressed Collectively, As Is the Case for Multi- Culturally Framed Systems of Social Or- Level Selection

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The Substance of Cultural Evolution: Expressed Collectively, As Is the Case for Multi- Culturally Framed Systems of Social Or- Level Selection The substance of cultural evolution: expressed collectively, as is the case for multi- Culturally framed systems of social or- level selection. While valid questions can be raised about ganization Smaldino’s characterization and differentiation of these three different levels, especially with Dwight W. Read regard to his thesis that group success in hu- Department of Anthropology and Department of man societies largely comes from “the organi- Statistics, University of California—Los Angeles, zation of a well-defined collection of differen- Los Angeles, CA 90094 tiated individuals all participating in a group- [email protected] level behavior” (p. 10-11), my focus here is on the phylogenetic trend going from solitary to Abstract: Models of cultural evolution need to structured groups and from individual to address not only the organizational aspects of hu- emergent to culturally framed behavior as we man societies, but also the complexity and struc- evolutionarily move towards our species, Ho- ture of cultural idea systems that frame their sys- mo sapiens, with its subdivision into highly tems of organization. These cultural idea systems determine a framework within which behaviors differentiated societies. The picture drawn by take place and provide mutually understood mean- Smaldino, using his wording for the limita- ings for behavior from the perspective of both tions of multilevel selection, “is not incorrect, agent and recipient that are critical for the coher- but it is incomplete” (p. 10). ence of human systems of social organization. The evolution of human social systems centers around the development of systems of Smaldino advances an argument similar to that organization that incorporate, rather than sup- of Lane et al. (2009) regarding the need to press, individual differentiation (Read 2012). make “a shift in perspective, from population Briefly, the phylogenetic trend towards in- thinking to organization thinking” (2009:12, creased individualization of behaviors that we emphasis in the original) by arguing that mod- see when we traverse the primates towards els of cultural evolution have not taken into Homo sapiens is paralleled by social com- account contextualization of human behavior plexity increasing exponentially with the num- through systems of organization that make ber of individualistic group members (Read human behavior more complex than just as 2012: Figure 4.3). This increase was accom- epiphenomena of individual level traits. This modated not only through neurological chang- leads him to consider three levels for modeling es (Dunbar 1998) but by changes in the struc- selection acting on traits: (1) individual traits, tural organization of social units that culminat- (2) multilevel traits (traits aggregated over be- ed, from a biological perspective, in reduction haviors engaged in collectively by interacting of the size of chimpanzee social units (Read group members), and (3) group traits ex- 2012) -- where chimpanzees social organiza- pressed through the institutionalized organiza- tion is often taken as a model for our ancestral tion of role-differentiated individuals (pp. 5-6). lineage when it diverged from the other pri- Group traits are, in his view, distinguishable mates (Chapais 2008) -- as a way to accom- by making use of the “specific organization of modate social complexity arising from highly [role] differentiated individuals” (p. 8), with individualized behavior (Read 2012: Figure selection acting on systems of organization 4.4). The social complexity introduced that maintain internal differentiation of indi- through increased individuality (what Smaldi- viduals, hence acting on emergent group be- no calls “individual differentiation”), was havior (p. 6) rather than on individual behavior eventually accommodated within the hominin ancestry of Homo sapiens by shifting from so- 1 Behavioral and Brain Sciences (2014) 37:3 cial systems based on face-to-face interaction organization of human societies (Read et al. that characterize the non-human primates 2009; Read 2012). While Smaldino correctly (which also leads to within group, aggregated places importance on systems of organization behavior upon which multi-level selection can that incorporate role differentiated individuals operate) to relational based systems of social in human societies, he does not discuss the fact organization (Smaldino’s institutionalized or- that these systems of organization need not be ganization of differentiated individuals) that emergent, but are often cultural constructions, are culturally framed (Read 2012). The fram- such as the culturally formed kinship systems ing through cultural idea systems is not in- that provide structure and organization in hu- cluded in Smaldino’s argument and is critical man societies, especially in the small scale so- to our understanding of human systems of so- cieties that were the evolutionary precursors of cial organization (cf. Leaf 2009). large scale human societies. Cultural kinship There is marked change in the ontological systems both define the societal boundaries level at which selection operates and fitness is and provide the structure and organization that measured concomitant with the sequence go- establishes the basis for the role differentiation ing from genetic traits expressed individually that Smaldino discusses (Leaf 2009; Leaf & and in isolation to traits expressed culturally Read 2012). The kinship terminologies that and collectively. The sequence begins with express the different systems of cultural kin- fitness measured by the number of reproducing ship relations are not emergent, as research on progeny, then when behavioral interaction the structural logic of kinship systems has among progeny is part of the trait, as occurs demonstrated (e.g., Read 1984, 2001, 2007, with biologically based altruistic behaviors, 2010; Leaf & Read 2012; Read et al. 2013). inclusive fitness becomes the measure of se- Terminologies are not the epiphenomena of lection. With multilevel selection acting on already patterned behavior -- as was assumed traits expressed collectively through group in some of the early research on human kin- structure (what Smaldino refers to as “collec- ship systems and has been assumed in ac- tive behavior” or “aggregate traits”), group- counts of human evolution (e.g., Chapais derived fitness averaged over group members 2008) -- but are constructed idea systems (Leaf is assigned. Next are emergent traits, such as & Read 2012) that provide conceptual organi- the linear, stable (e.g., Isbell & Young 1993, zation for the small scale societies from which Range & Noë 2002), matrilineally inherited present day human societies have evolved. female dominance hierarchies (Kapsalis 2004) Kinship terminology systems have a genera- that emerge in many of the species making up tive logic to them that can be expressed the Cercopithecines from a female “placing” through a “grammar,” and differences among her biological daughter immediately below her kinship terminology systems are derived from in the dominance ranking (e.g., le Roux et al. systematic differences in the generative logic 2011; see Read 2012 and references therein). of kinship terminologies (Read 2013). Emergent traits, for Smaldino, provide transi- Models of cultural evolution need to ad- tion from the uniformity of group behavior dress not only the organizational aspects dis- assumed in multilevel selection to organized, cussed by Smaldino, but also the complexity role differentiated behavior through which and structure of cultural idea systems that group level traits are expressed. Here fitness is frame the systems of organization that are cen- measured directly through the group-level tral to human societies. These cultural idea trait. systems determine a framework within which Missing from this sequence, though, is the behaviors take place and provide mutually un- critical “next step” leading to the structure and derstood meanings for behavior from the per- 2 spective of both agent and recipient that are pological relativism (pp. 78-117). Urbana: critical for the coherence of human systems of University of Illinois Press. social organization. Read, D. (2007). Kinship theory: A paradigm shift. Ethnology, 46(4), 329-364. References Read, D. (2010). The algebraic logic of kin- Chapais, B. (2008). Primeval kinship: How ship terminology structure. Behavioral and pair bonding gave birth to human society. Brain Sciences, 33(5), 399-400. Cambridge: Harvard University Press. Read, D. (2012). How culture makes us hu- Dunbar, R. I. M. (1998). The social brain hy- man: Primate evolution and the formation pothesis. Evolutionary Anthropology, 6, of human societies Walnut Creek: Left 178-190. Coast Press. Isbell, L., & Young, T. (1993). Social and eco- Read, D. (2013). A new approach to forming a logical influences on activity budgets of typology of kinship terminology systems: vervet monkeys, and their implications for From Morgan and Murdock to the present. group living. Behavioral Ecology and So- Structure and Dynamics, 6(1). ciobiology, 32, 377-385. http://www.escholarship.org/uc/item/0ss6j Kapsalis, E. (2004). Matrilineal kinship and 8sh primate behavior. In B. Chapais & C. M. Read, D., Lane, D., & van der Leeuw, S. Berman (Eds.), Kinship and behavior (2009). The innovation innovation. In D. inprimates (pp. 153-176). Oxford: Oxford Lane, D. Pumain, S. van der Leeuw & G. University Press. West (Eds.), Complexity perspectives in Lane, D., Maxfield, R. M., Read, D., & van innovation and social change
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