Kevin N. Laland
University of St AndrewsSchool of Biology
Bute Building, Queen's Terrace
St Andrews, KY16 9TS
United Kingdom
Website
Abstracts (first author)
Genetic control of non-genetic inheritance: fact or fallacy?
Summary:
The foundation of the Modern Synthesis placed the gene at the centre of evolutionary explanations of biology, largely because at the time Mendelian genetics appeared to be the only general inheritance system. More recently, other non-genetic inheritance (henceforth NGI) systems (epigenetic inheritance, parental effects, ecological inheritance, social transmission and cultural inheritance) have been identified and been found to be widespread, raising questions about whether, and how, non-genetic inheritance might change the character of biological evolution. Here we draw on established empirical and theoretical findings from the cultural evolution, gene-culture coevolution, evolution of plasticity, and niche construction, literatures to illustrate ten ways in which non-genetic inheritance affects biological evolution. These include the findings that NGI systems can generate non-random (adaptive) variants; that they change the rate and dynamics of evolution, the pathways of information flow, and equilibria reached; that they alter the frequencies and spatial distribution of phenotypes; that they can propagate maladaptive variants; and that they change conceptions of fitness. These findings leave untenable the claims that non-genetic inheritance is under genetic control and as a consequence does not change the evolutionary process in biologically meaningful ways. Our analysis supports arguments for a broadening of current conceptions of biological evolution.