The negotiated organism: Inheritance, development, and the method of difference

Abstract

The modern synthesis theory of evolution is predicated upon a conception of the relationship between inheritance and development that can be called the 'two spaces and a barrier' view. The view preserves a privileged role for genes: they are discrete units of inheritance, and the principal causes of phenotypes. It also explicitly excludes development, behaviour, learning, and social interactions from the production of genuine evolutionary novelties. It is argued here that the two spaces and a barrier view has been generated, to a significant degree, by a specific mode of causal inference: the 'method of difference'. The method of difference is, however, inapplicable, and indeed misleading, given what we now know about the function of genes in development and inheritance. This realization should cause us to rethink the role of genes, genomes, and organisms in evolution. In particular, it should lead us to consider that the processes occurring within the lifetime of organisms, including development, behaviour and learning, make direct contributions to evolution, unmediated by genes. © 2013 The Linnean Society of London.