Did Human Culture Emerge in a Cultural Evolutionary Transition in Individuality?

Steven L Kuhn,Claes Andersson,Richard E Michod,Dinah R Davison

doi:10.1007/s13752-021-00382-x

Abstract

Evolutionary Transitions in Individuality (ETI) have been responsible for the major transitions in levels of selection and individuality in natural history, such as the origins of prokaryotic and eukaryotic cells, multicellular organisms, and eusocial insects. The integrated hierarchical organization of life thereby emerged as groups of individuals repeatedly evolved into new and more complex kinds of individuals. The Social Protocell Hypothesis (SPH) proposes that the integrated hierarchical organization of human culture can also be understood as the outcome of an ETI—one that produced a “cultural organism” (a “sociont”) from a substrate of socially learned traditions that were contained in growing and dividing social communities. The SPH predicts that a threshold degree of evolutionary individuality would have been achieved by 2.0–2.5 Mya, followed by an increasing degree of evolutionary individuality as the ETI unfolded. We here assess the SPH by applying a battery of criteria—developed to assess evolutionary individuality in biological units—to cultural units across the evolutionary history of Homo. We find an increasing agreement with these criteria, which buttresses the claim that an ETI occurred in the cultural realm.

Highlights

Traditional behaviors are found in many animal species (Galef and Laland 2005; Allen 2019), but only in Homo have they coalesced into integrated and shared cultural systems (e.g., Andersson et al 2014a; Smaldino 2014; Richerson et al 2016; Buskell et al 2019; Read and Andersson 2019), and only Homo has come to specialize in maintaining and acting within such systems
Boundaries in a social space here play the role that physical boundaries play in biology, and, social spaces are frequently associated with physical territories, that is not always the case
In the Social Protocell Hypothesis (SPH) case, the heritable information is cultural rather than genetic, and we see the sociont as informationally unique to the extent that it possesses its own stable, independent, and heritable set of traditions or cultural components

Summary

Introduction

Traditional behaviors are found in many animal species (Galef and Laland 2005; Allen 2019), but only in Homo have they coalesced into integrated and shared cultural systems (e.g., Andersson et al 2014a; Smaldino 2014; Richerson et al 2016; Buskell et al 2019; Read and Andersson 2019), and only Homo has come to specialize in maintaining and acting within such systems (e.g., via expanded cognitive and metacognitive functions; Sherwood et al 2008; Csibra and Gergely 2011; Whiten and Erdal 2012; Shea et al 2014; Sherwood and Gómez-Robles 2017; Dunstone and Caldwell 2018). The operation of this cultural system, which is much wider and older than its individual human stewards, who depend on it for their survival (e.g., Boyd and Richerson 2000; Henrich and McElreath 2003) This uniquely human “cultural community” embodies an emergent ecological strategy that cannot be reduced either to its learned or its genetic components (1992). We will use the most commonly applied criteria as reviewed by Hanschen et al (2017): spatial boundaries, informational uniqueness, informational homogeneity, indivisibility, group-level adaptations, division-of-labor, and the applicability of a specific kind of multilevel selection termed multilevel selection 2 These criteria identify features that are generated by and/or enabling of group-level selection, and that are thereby likely to arise during an ETI, but unlikely to be seen otherwise (in particular together and in a highly developed state). We emphasize the Plio-Pleistocene origin of the sociont via the social protocell, its early evolutionary history (primarily in the Oldowan), and, we consider trends across the evolution of Homo during the Pleistocene

Objectives

Results

Discussion

Conclusion