Eric Edeline and Nicolas LoeuillePlease use the format "First name initials family name" as in "Marie S. Curie, Niels H. D. Bohr, Albert Einstein, John R. R. Tolkien, Donna T. Strickland"
<p>Harvesting may drive body downsizing along with population declines and decreased harvesting yields. These changes are commonly construed as direct consequences of harvest selection, where small-bodied, early-reproducing individuals are immediately favoured. However, together with directly selecting against a large body size, harvesting and body downsizing alter many ecological features, such as competitive and trophic interactions, and thus also indirectly alter natural selection acting back on body sizes through eco-evolutionary feedback loops (EEFLs). We start this essay by reviewing the conditions under which natural selection favours either larger or smaller body sizes. Then, we analyse simple EEFLs in which one-dimensional density-dependent natural selection acts either antagonistically or synergistically with direct harvest selection on body size. Antagonistic feedbacks favour body-size stasis but erode genetic variability and associated body-size evolvability, and may ultimately impair population persistence and recovery. In contrast, synergistic feedbacks drive fast evolution towards smaller body sizes and favour population resilience, but may have far-reaching bottom-up or top-down effects. We illustrate the further complexities resulting from multiple environmental feedbacks using a co-evolving predator-prey pair. In this case, outcomes from EEFLs depend not only on densities, but also on whether prey sit above or below the optimal predator/prey body-size ratio, and whether prey have a higher or lower body-size evolvability than predators. EEFLs improve our ability to understand and predict nature's response to harvesting, but their integration into the research agenda will require a full consideration of the effects and dynamics of natural selection.</p>
Body size, Co-evolution, Competition, Eco-evolutionary feedbacks, Fisheries, Harvesting, Natural selection, Predation.
Biodiversity, Community ecology, Competition, Eco-evolutionary dynamics, Evolutionary ecology, Food webs, Interaction networks, Life history, Population ecology, Theoretical ecology
