INTRODUCTION to CHAPTER SEVEN
This chapter introduces the ideas of group selection and multi-level selection, and defines the interactor.
Thanks to the work of David Sloan Wilson, Elliott Sober and others, the concept of group selection has been rehabilitated in mainstream biology. To understand group selection it is vital to make a distinction between objects of selection (interactors) and outcomes of selection in a population (the pool of replicators). Group selection means that groups are objects of selection, and thus interactors. For this to happen, variation within groups must be less than variation between groups.
Genetic group selection refers to variation in regard to genes and changes in the gene pool of a population. Cultural group selection refers to variation in regard to cultural replicators (habits, customs, and routines) and outcomes in regard to their distribution.
In human evolution, genetic intermixing between groups may have diminished the effects of genetic group selection, whereas processes such as conformism may have created sufficient group homogeneity for cultural group selection to work.
Up to this point we draw on existing literature. From about page 103 we make a new contribution. We ask what are the features that make a selected group (in viable group selection) relatively coherent, cohesive and long-lasting. Such groups must be more than mere aggregates of individuals.
To this end we modify David Hull’s classic definition of an interactor. Our definition appears on pages 106-7. Among other things, it differentiates an interactor from its environment, and shows the dependence of component replicators on their interactor. In turn, replication depends on interaction between the interactor and its environment.
Finally we discuss how business organizations can be interactors, and how their component routines can replicate. Much replication in the social world is through diffusion, but in the case of firm spin-offs replication involves offspring replicators.
1. What are the conditions for group selection to occur?
2. In what respects can groups be more than the sum of their members?
3. What are interactors?
4. What are possible mechanisms of replication in the social world?