The Evolution of Conformist Transmission and the Emergence of Between-Group Differences

doi:10.1016/S1090-5138(98)00018-X

Evolution and Human Behavior

Volume 19, Issue 4, July 1998, Pages 215-241

https://doi.org/10.1016/S1090-5138(98)00018-X Get rights and content

Abstract

Unlike other animal species, much of the variation among human groups is cultural: genetically similar people living in similar environments exhibit strikingly different patterns of behavior because they have different, culturally acquired beliefs and values. Such cultural transmission is based on complex, derived psychological mechanisms that are likely to have been shaped by natural selection. It is important to understand the nature of these evolved psychological mechanisms because they determine which beliefs and values spread and persist in human groups. Boyd and Richerson showed that a tendency to acquire the most common behavior exhibited in a society was adaptive in a simple model of evolution in a spatially varying environment, because such a tendency increases the probability of acquiring adaptive beliefs and values. Here, we study the evolution of such “conformist transmission” in a more general model in which environments vary in both time and space. The analysis of this model indicates that conformist transmission is favored under a very broad range of conditions, broader in fact than the range of conditions that favor a substantial reliance on social learning. The analysis also suggests that there is a synergistic relationship between the evolution of imitation and the evolution of conformism. We conclude by examining the role of conformism in explaining the maintenance of cultural differences among groups.

Section snippets

Cultural evolution as a problem in population dynamics

In humans, social learning gives rise to cumulative cultural change not seen in other animals, and, as a result, understanding human evolution requires new principles not relevant to the study of other species (Boyd and Richerson 1996). This does not mean that humans have somehow transcended biology. Quite to the contrary, we can construct a foundation for emergent cultural phenomena by understanding the evolution of complex cognitive adaptations. Evolutionary psychology proposes that all

Modeling the evolution of social learning and conformist transmission

We assume that the central adaptive problem facing individuals is how to best use environmental cues to choose behavior when the environment changes in space and time. For the purpose of modeling this situation, we have divided environmental cues into two kinds: nonsocial and social. Nonsocial cues predict the current environmental state, but these cues are imperfect. Relying on the nonsocial cues alone will allow individuals to do better than random, but will sometimes lead to errors.

Results

By systematically varying ρ, the accuracy of environmental information, m, the migration rate, ϵ, the degree of environmental stability, and n, the number of subpopulations, we have learned several important things about the evolution of social learning and conformist transmission. First, the degree of reliance on social learning (L) depends on strongly on the accuracy of environmental information (ρ) and the frequency of environmental fluctuations (1 − ϵ). The evolution of high values of L

Why is conformist transmission important?

Conformist transmission accounts for the fact that there is “heritable” cultural variation among human groups. Humans live in cultural groups in which group members tend to believe similar things about the world and behave in similar ways. Individuals in neighboring groups tend to believe different things and behave in different ways, even though people from different groups may interact and even intermarry. Conformist transmission generates a population-level process that creates and maintains

Conclusions

In the preceding discussion, we have reached several conclusions regarding the evolution of social learning, conformist transmission, and the emergence of within-group similarities and between group differences. We summarize them as follows:

1.
Our model indicates that conformist transmission is favored by selection under a wide range of conditions. Conformist transmission evolves in fluctuating environments; it evolves when the accuracy of environmental information is poor and when it is fairly

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Original ArticlesThe Evolution of Conformist Transmission and the Emergence of Between-Group Differences

Abstract

Section snippets

Cultural evolution as a problem in population dynamics

Modeling the evolution of social learning and conformist transmission

Results

Why is conformist transmission important?

Conclusions

Ethology and Sociobiology

Ethology and Sociobiology

Darwinism and Human Affairs

Introduction

Game Theory and the Social Contract

Anthropology and Modern Life

Culture and the Evolutionary Process

The evolution of ethic markers

Cultural Anthropology

Social learning as an adaptation

Lectures on Mathematics in the Life Sciences