Data from: Ontogeny and consistent individual differences mediate trophic interactions

Ecologists use species traits to predict individual responses to environmental change, and ultimately to understand the composition of biological communities. However, this ignores known and substantial intraspecific variation that can have important consequences for species interactions and community composition. This within-species variation results from two distinct sources: ontogeny and consistent individual differences. Ontogeny and consistent differences interact to produce phenotypes, but the community-level consequences of this interaction have not been studied. Using larval dragonfly communities I investigate patterns of intraguild predation by manipulating (1) consistent individual differences in activity rate, and (2) the ontogeny of the focal and interacting species. I show that activity rate is a consistent individual trait, but that the effect of activity rate on intraguild predation depends on the functional role of an organism in the community (predator or prey). An organism's functional role itself varies across ontogeny of both the focal and interacting individuals. I suggest that ontogeny and consistent individual differences interact to produce intraspecific variation, with consequences for species interactions, communities, and eco-evolutionary dynamics.生态学家常利用物种性状（species traits）预测生物个体对环境变化的响应，并最终解析生物群落的组成格局。然而，此类研究往往忽略了已被广泛证实且影响显著的种内变异（intraspecific variation），这类变异对物种互作与群落组成具有重要意义。此类种内变异源自两个截然不同的来源：个体发育（ontogeny）与个体间稳定差异。个体发育与个体间稳定差异共同作用塑造了生物表型，但二者互作对群落层面的影响尚未得到研究。本研究以蜻蜓幼虫群落为研究对象，通过操控两项变量探究集团内捕食（intraguild predation）模式：其一为个体运动速率的稳定差异，其二为目标物种与互作物种的个体发育阶段。研究结果表明，运动速率属于个体稳定性状，但其对集团内捕食的影响取决于该生物在群落中的功能角色（捕食者或猎物）。生物的功能角色本身会随目标个体与互作个体的个体发育进程发生变化。本研究提出，个体发育与个体间稳定差异共同作用产生种内变异，这一过程会对物种互作、群落结构以及生态-进化动态（eco-evolutionary dynamics）产生影响。