Abstract：
AbstractIntraspecific trait variation has been increasingly recognized as an important factor in determining species interactions and diversity. Eco-evolutionary models have studied the distribution of trait values within a population that changes over the generations as a result of selection and heritability. Nonheritable traits that can change within the lifetime, such as behavior, can cause trait-mediated indirect effects, often studied by modeling the dynamics of a homogeneous trait. Complementary to these approaches, we study the distribution of traits within a population and its dynamics on short timescales due to ecological processes. We consider several mechanisms by which the trait distribution can shift dynamically: phenotypic plasticity within each individual, differential growth among individuals, and preferential consumption by the predator. Through a simple predator-prey model that explicitly tracks the trait distribution within the prey, we identify the density and trait effects from the predator. We show that the dynamic shift of the trait distribution can lead to the modification of interaction strength between species and result in otherwise unexpected consequences. A particular example is the emergent promotion of the prey by the predator, where the introduction of the predator causes the prey population to increase rather than decrease.
摘要：
种内性状变异越来越被认为是决定物种相互作用和多样性的重要因素。生态进化模型研究了种群内性状值的分布，该性状值由于选择和遗传力而在世代中发生变化。可以在一生中改变的不可遗传特征，比如行为，可以引起性状介导的间接效应，通常通过对同质性状的动力学建模来研究。这些方法的补充，我们研究了由于生态过程而导致的种群特征分布及其在短时间尺度上的动态。我们考虑了性状分布可以动态变化的几种机制：每个个体内的表型可塑性，个体之间的差异增长，以及捕食者的优惠消费。通过一个简单的捕食者-猎物模型，明确地跟踪猎物内部的性状分布，我们确定了捕食者的密度和性状效应。我们表明，性状分布的动态变化会导致物种之间相互作用强度的改变，并导致其他意想不到的后果。一个特别的例子是捕食者对猎物的紧急推动，捕食者的引入导致猎物数量增加而不是减少。
