资源环境科技发展态势分析平台

When prey experience size‐based harvesting by predators, they are not only subject to selection due to larger individuals being preferentially harvested but also selection due to reductions in population density. Density‐dependent selection represents one of the most basic interactions between ecology and evolution. Yet, the reduction in density associated with exploitation has not been tested as a possible driving force of observed evolutionary changes in populations harvested size‐dependently. Using an artificial selection experiment with a mixture of Daphnia clones, we partition the evolutionary effects of size‐based harvesting into the effects of removing large individuals and the effects of lowering the population density. We show that both size selection and density‐dependent selection are significant drivers of life‐history evolution. Importantly, these drivers affected different life‐history traits with size‐selective harvesting selecting for slower juvenile growth rates and a larger size at maturity, and low‐density selecting for reduced reproductive output.