Modelling the influence of parental effects on gene‐network evolution

International audienceUnderstanding the importance of non-genetic heredity in the evolutionary process is a major topic in modern evolutionary biology. We modified a classical gene network model by allowing parental transmission of gene expression, and studied its evolutionary properties through individual-based simulations. We identified ontogenetic time (i.e. the time gene networks have to stabilize before being submitted to natural selection) as a crucial factor in determining the evolutionary impact of this phenotypic inheritance. Indeed, fast-developing organisms display enhanced adaptation and greater robustness to mutations when evolving in presence of non-genetic inheritance. In contrast, in our model, long development reduces the influence of the inherited state of the gene network. Non-genetic inheritance thus had a negligible effect on the evolution of gene networks when the speed at which transcription levels reach equilibrium is not constrained. Nevertheless, simulations show that inter-generational transmission of the gene network state negatively affects the evolution of robustness to environmental disturbances for either fast or slow developing organisms. Therefore, these results suggest that the evolutionary consequences of non-genetic inheritance might not be sought only in the way species respond to selection, but also on the evolution of emergent properties (such as environmental and genetic canalization) in complex genetic architectures