Data from: Digging through model complexity: using hierarchical models to uncover evolutionary processes in the wild

The growing interest for studying questions in the wild requires acknowledging that eco-evolutionary processes are complex, hierarchically structured and often partially observed or with measurement error. These issues have long been ignored in evolutionary biology, which might have led to flawed inference when addressing evolutionary questions. Hierarchical modelling (HM) has been proposed as a generic statistical framework to deal with complexity in ecological data and account for uncertainty. However, to date, HM has seldom been used to investigate evolutionary mechanisms possibly underlying observed patterns. Here, we contend the HM approach offers a relevant approach for the study of eco-evolutionary processes in the wild by confronting formal theories to empirical data through proper statistical inference. Studying eco-evolutionary processes requires considering the complete and often complex life histories of organisms. We show how this can be achieved by combining sequentially all life histories components and all available sources of information through HM. We demonstrate how eco-evolutionary processes may be poorly inferred or even missed without using the full potential of HM. As a case study, we use the Atlantic salmon and data on wild marked juveniles. We assess a reaction norm for migration and two potential trade-offs for survival. Overall, HM has a great potential to address evolutionary questions and investigate important processes that could not previously be assessed in laboratory or short time-scale studies.

野外环境中研究问题的关注度与日俱增，这要求我们认识到：生态进化过程（eco-evolutionary processes）兼具复杂性与层级结构化特征，且常存在观测不全或伴随测量误差的情况。长期以来，进化生物学领域对这类问题鲜有关注，这可能导致在解答进化相关问题时出现带有偏差的推断。层级建模（Hierarchical Modelling, HM）作为一种通用统计框架被提出，用于处理生态数据中的复杂性并量化不确定性。然而迄今为止，层级建模极少被用于探究可能支撑观测模式的进化机制。本文认为，层级建模方法可为野生环境中生态进化过程的研究提供有效路径——通过严谨的统计推断将形式化理论与实证数据相对接。

研究生态进化过程需要考量生物体完整且通常极为复杂的生活史（life history）。我们展示了如何通过层级建模，将所有生活史组分与所有可获得的信息源依次整合，从而达成这一研究目标。我们证明了，若未充分发挥层级建模的全部潜力，对生态进化过程的推断可能会存在严重偏差，甚至完全遗漏相关过程。作为案例研究，我们以大西洋鲑（Atlantic salmon）及野生标记幼鲑的相关数据为研究对象，评估了迁移反应规范（reaction norm）以及两种与存活相关的潜在权衡（trade-off）。

总体而言，层级建模具备极大潜力，可用于解答进化相关问题，并探究此前无法在实验室或短时间尺度研究中开展评估的关键过程。