The cultural evolution of socially situated cognition

The intro to Liane’s paper.

Other papers in this issue explore how cognition is shaped by the social matrix in which it is embedded. In this paper the reader is invited to take a step back and consider the dynamics that emerge when cognitive agents do not just learn from one another, but ‘put their own spin on’ what they learn, make sense of it in their own terms, and then express or implement their ‘take’ on the ideas back to others. Elements of culture start to create niches for one another. They become more complex with time, such that they might be thought of as constituting cultural lineages.

Some treat cultural change as merely a facet or dimension of biological evolution (Jablonka & Lamb, 2006). Others, while not denying that culture has a dramatic impact on biological life, argue that culture constitutes a form of evolution in its own right, a second evolutionary process. On Earth the two are deeply intertwined (as illustrated by phenomena such as genetic assimilation, the Baldwin effect, and the fact that biological life had to come into being before culture could take hold). But in principle they need not be. For example, in a computer program in which artificial agents invent and imitate ideas for new gestures, but neither die nor give birth, there is still evolution (Gabora, 1995). It is not the agents’ physical form that is evolving, but their ideas. Fit gestures get imitated, and spread through the artificial society, while unfit gestures do not, such that over time the distribution of gestures implemented by agents becomes fitter. Indeed, cultural traits can be said to undergo descent with modification, and on the face of it cultural change is reminiscent of natural selection. It exhibits phenomena studied by population geneticists such as adaptation, punctuated equilibrium (Orsucci, in press), and drift (Bentley et al., 2004, Durham, 1991 and Gabora, 1995), as well as features referred to by Mesoudi, Whiten, and Laland (2004) as “key Darwinian properties”, including variation, competition, and inheritance. Cultural change is also cumulative; humans have a propensity to not just generate novelty but build on it cumulatively, adapting old ideas to new circumstances (the Ratchet effect). One individual modifies the basic idea of a cup by giving it a flat enough bottom to stay put when not in use, another adds a handle, making it easier to grasp, and yet another adds a spout, making it easier to pour from. Moreover, this cumulative change is adaptive. With each instantiation, the basic idea remains the same but the details change to make it more useful with respect to the prevailing situation or need. It is also complex and open-ended; there is no limit to the cultural novelty that can be generated.

This paper attempts to answer the question of whether the transmission and transformation of information across individuals occurs through a Darwinian process, and in what sense (if any) culture can rightly be said to ‘evolve’. We begin by examining why organisms do not inherit acquired characteristics, and how this impacts their evolution. This is key because acquired change is inherited in culture, though note that here ‘inherited’ merely means transmitted or ‘passed on’ without implying genetic mediation. To the extent that not inheriting acquired characteristics is central to how organisms evolve, answers from biology will not translate to culture. Noting that current origin of life theories suggest that the earliest life forms, referred to as protocells, also inherited acquired characteristics, we examine the hypothesis that the mechanisms by which culture evolves are more akin to those underlying the evolution of protocells than modern-day life.