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Dispersal among local communities is fundamental to the metacommunity concept but is only important to the metacommunity structure if dispersal causes distortions of species abundances away from what local ecological conditions favour. We know from much previous work that dispersal can cause such abundance distortions. However, almost all previous theoretical studies have only considered one species alone or two interacting species (e.g. competitors or predator and prey). Moreover, a systematic analysis is needed of whether different dispersal strategies (e.g. passive dispersal versus demographic habitat selection) result in different abundance distortion patterns, how these distortion patterns change with local food web structure, and how the dispersal propensities of the interacting species might evolve in response to one another. In this article, we show using computer simulations and analytical models that abundance distortions occur in simple food webs with both passive dispersal and habitat selection, but habitat selection causes larger distortions. Additionally, patterns in the evolution of dispersal propensity in interacting species are very different for these two dispersal strategies. This study identifies that the dispersal strategies employed by interacting species critically shape how dispersal will influence metacommunity structure. This article is part of the theme issue 'Diversity-dependence of dispersal: interspecific interactions determine spatial dynamics'. [ABSTRACT FROM AUTHOR]

The importance of dispersal rates and distances has long been appreciated by ecologists and evolutionary biologists. An emerging field of research is revealing how temporal variation in dispersal can substantially influence ecological and evolutionary outcomes. We review how dispersal rates can temporally vary substantially in many ecosystems, a pattern that is particularly well‐documented for aquatic organisms but is likely pervasive in terrestrial ecosystems as well. We then synthesize the effects of temporal variation in dispersal on five key ecological and evolutionary processes: 1) metapopulation dynamics, 2) local adaptation, 3) range limits and range expansions, 4) species coexistence and 5) metacommunity dynamics. Our review demonstrates that temporal variation in dispersal is more than just statistical 'noise' but can in fact lead to different outcomes than expected were dispersal temporally constant. For example, increasing the magnitude of temporal variation in dispersal can lead to lower metapopulation growth rates, permit greater local adaptation, facilitate and accelerate range expansion, increase regional coexistence, and alter local and regional species diversity. These effects of temporal variation in dispersal can inform conservation and natural resource management decisions such as prioritization in spatial planning, management of spillover from domesticated or captive populations into native populations, and the design of effective control strategies for invasive species. [ABSTRACT FROM AUTHOR]

Humans greatly influence the ecosystems they live in and the lives of a wide range of taxa they share space with. Specifically, human hunting and harvesting has resulted in many species acclimating via diverse behavioral responses, often quite rapidly. This review provides insights into how hunting and harvesting can elicit behavioral changes. These responses emerge from a species' previous and evolving ability to assess risk imposed by hunters and respond accordingly; a predator–prey game thus ensues, where both players may change tactics over time. If hunting is persistent, and does not result in the taxa's extirpation, species are expected to develop adaptations to cope with hunting via natural selection by undergoing shifts in morphology and behavior. This review summarizes the various ways that human hunting intentionally and incidentally alters such evolutionary changes. These changes in turn can influence other species interactions and whole ecosystems. Additionally, alterations in behaviors can provide useful indicators for conservation and evolutionarily enlightened management strategies, and humans should use them to gain insights into our own socio-economic circumstances. [ABSTRACT FROM AUTHOR]

Reproductive mode may strongly impact adaptation in spatially varying populations linked by dispersal, especially when sexual and clonal offspring differ in dispersal. We determined how spatial structure affects adaptation in populations with mixed clonal and sexual reproduction. In a source-sink quantitative genetic deterministic model (with stabilizing selection around different optima), greater clonal reproduction or parent-offspring association (a measure of the part of the parent's phenotype other than the additive genetic component inherited by clonal offspring) increased the selective difference (difference between phenotypic optima) allowing sink populations to adapt. Given dispersal differences between clonally and sexually produced juveniles, adaptation increased with an increasing fraction of clonal dispersers. When considering migrational meltdown, partially clonal reproduction reduced cases where dispersal caused habitat loss. Stochastic individual-based simulations support these results, although the effect of differential dispersal was reversed, with decreased clonal dispersal allowing greater adaptation. These results parallel earlier findings that for an instantaneous shift in phenotypic optimum, increasing clonality allowed population persistence for a greater shift; here, selective change is spatial rather than temporal. These results may help explain the success of many partially clonal organisms in invading new habitats, complementing traditional explanations based on avoiding Allee effects. [ABSTRACT FROM AUTHOR]