Mother nature's tolerant ways: why non-genetic inheritance has nothing to do with evolution

Recently a number of theorists have suggested that evolution can use non-genetic or environmental inheritance to pass on adaptations (e.g. Mameli, 2004). Furthermore, it has been suggested that nongenetic, or environmental factors, can play a central role in the process of evolution that is not captured by the neo-Darwinian view which places natural selection centre-stage (e.g. Odling-Smee, Laland & Feldman, 2003). In this paper we present and clarify neo-Darwinian theory and then take issue with the notions of contemporary gene-centred selection and inheritance that non-genetic inheritance theorists have used. We claim that they have misunderstood the distinction and relationship between intrinsic and extrinsic inheritance and we clarify this with a number of examples from the behavioural and biological sciences. According to this analysis there is no such thing as biologically independent nongenetic inheritance, all extrinsic inheritance is a consequence of traits and dispositions that are intrinsic to an organism and intrinsic design can only be explained through neo-Darwinism. We point to the implications this view has for current conceptions of cultural evolution

Evidence from reaction times for an anticipatory process in symbolic delayed matching-to-sample

It was predicted that a delay between sample ofset and comparison onset in symbolic delayed matching-to-sample (DMTS) would allow time for the anticipatory retrieval of the correct comparison so that the match/no match status of the presented comparison could be decided more swiftly. The relation between delay and reaction time (RT) was explored in participants after they had been similarly tested, as a control, on identity DMTS using the same stimuli. In most participants there was the predicted inverse relation between delay and RT in symbolic DMTS, but no such relation in identity DMTS. Subsequently an arithmetic test, designed to allow a simple calculation before or after presentation of the comparison, was used to demonstrate an analogous effect of a delay on RT

Evolution of imprinting: imprinted gene function in human disease [online encyclopaedia contribution]

A subset of genes in mammals, known as imprinted genes, show a conditional expression strategy in which transcription depends on an allele’s parental origin. Several explanations have been advanced to explain this phenomenon and these, with varying levels of success, predict the functions of imprinted genes. After outlining these explanations, we summarize what is known about human genetic disorders involving abnormal expression of imprinted genes and ask what this can tell us about the evolution of imprinting

Evolutionary biology: contemporary and historical reflections upon core theory

In this chapter, we make some general comments about the nature of scientific explanation and use them to contextualize recent debates within evolutionary biology about the adequacy of what is sometimes termed standard evolutionary theory. These comments serve to introduce the aims of the book and we then summarize the chapters to follow, relating them to the opening themes