In recent years the potential for evolutionary change to drive ecological dynamics, and vice versa, has been widely recognized. However, the convincing examples of eco-evolutionary dynamics mainly stem from highly artificial experimental systems, with conspicuously few examples contributed by field systems. While rarely considered in the eco-evolutionary literature, the genefor-gene hypothesis inherently recognizes the tight link between evolutionary and ecological dynamics. The boom-and-bust dynamics of some agricultural pathogens are an extreme demonstration of this. In this perspective, we place plant-pathogen systems in a spatial ecoevolutionary framework, which recognizes that ecology and evolution are tightly linked, take place at the same time scale and are strongly influenced by spatial structure. Specifically, we i) exemplify how the ecological process of dispersal modifies rapid local coevolutionary dynamics and thereby shapes spatial variation in resistance, infectivity, and local adaptation; and ii) illustrate how the outcome of coevolution (spatial distribution in resistance, infectivity and local adaptation) drives ecological metapopulation processes. Overall, we conclude that both agricultural and wild pathosystems provide a unique illustration of the high relevance of spatial eco-evolutionary feedback in understanding species interactions.
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Eco-evolutionary dynamicsThe potential for eco-evolutionary feedback loops in determining the dynamics of populations has been increasingly recognized in recent years Post and Palkovacs 2009;Schoener 2011;Ellner 2013;Reznick 2013). This feedback is comprised of two pathways: the ecology-to-evolution pathway, where ecological change generates genetic and phenotypic responses (natural selection); and the evolution-to-ecology pathway, where genetic and phenotypic change affects ecological quantities, often measured as the population growth rate. However, while the potential of species to adapt to ecological conditions has long been realized, the effect of rapid evolutionary change on ecological dynamics is still poorly understood. In part, this is due to the fact that traditionally evolution has been viewed as a slow process operating at a timescale that is very different from ecological time (Slobodkin 1961;Hutchinson 1965). From such a perspective, ecological dynamics would play out as if evolution was not occurring, as evolutionary change would be non-significant on the ecological time-scale. Likewise, short-term fluctuations in ecological variables would average out over evolutionary time-scales, and only the long-term average would affect evolution (Hairston et al. 2005). However, it is becoming increasingly clear that evolutionary change can be extremely rapid, and there are compelling examples of this in a diversity of traits ranging from life-histories to behaviour and physiology (as reviewed in Thompson 2013). Moreover, a rapidly increasing number of studies suggest that eco-evolutionary dynamics and feedbacks have the potential to play a promin...