Interactions between fitness components across the life cycle constrain competitor coexistence
Interactions between fitness components across the life cycle constrain competitor coexistence
复制标题
整个生命周期中健身组件之间的相互作用限制了竞争对手的共存
DOI：
10.1111/1365-2656.13927
复制
发表时间：
2023
影响因子：
4.8
通讯作者：
Siepielski, Adam M.
中科院分区：
文献类型：
--
作者：
Gómez‐Llano, Miguel;Boys, Wade A.;Ping, Taylor;Tye, Simon P.;Siepielski, Adam M.
许多机制可以促进竞争者共存。然而，这些机制往往被孤立地考虑。因此，形成共存的多种机制联合收割机是否结合起来促进或限制物种共存仍然是一个悬而未决的问题。在这里，我们的目标是了解多种机制如何在生命阶段内和生命阶段之间相互作用，以确定频率依赖的种群增长，我们在三个湖泊进行了实地实验，操纵两种Enallagmadamselfly物种的相对频率，以评估人口贡献三种机制影响不同的健身组件在整个生命周期：对个人的增长率，捕食形成死亡率的影响，资源竞争和交配骚扰决定生育力。然后，我们使用一个人口模型，该模型包含了生命阶段之间的结转效应，以分解每个适应度分量产生频率依赖的种群增长的相对影响。该分解表明，当一个物种稀少时，适应度分量结合在一起会增加种群增长率，但当另一个物种稀少时，它们结合在一起会降低种群增长率，导致预测排除在大多数湖泊。因为健身组件之间的相互作用和生命阶段之间的种群之间的变化，这些结果表明，本地共存是种群特异性的。此外，我们表明，多种机制并不一定会增加竞争者共存，因为它们也可以联合收割机产生排斥。识别其他系统中的共存机制将需要更多地关注确定整个生命周期中不同适应度组件的贡献，从而以捕获群体水平变化的潜力的方式塑造竞争对手共存。
Numerous mechanisms can promote competitor coexistence. Yet, these mechanisms are often considered in isolation from one another. Consequently, whether multiple mechanisms shaping coexistence combine to promote or constrain species coexistence remains an open question.Here, we aim to understand how multiple mechanisms interact within and between life stages to determine frequency‐dependent population growth, which has a key role stabilizing local competitor coexistence.We conducted field experiments in three lakes manipulating relative frequencies of twoEnallagmadamselfly species to evaluate demographic contributions of three mechanisms affecting different fitness components across the life cycle: the effect of resource competition on individual growth rate, predation shaping mortality rates, and mating harassment determining fecundity. We then used a demographic model that incorporates carry‐over effects between life stages to decompose the relative effect of each fitness component generating frequency‐dependent population growth.This decomposition showed that fitness components combined to increase population growth rates for one species when rare, but they combined to decrease population growth rates for the other species when rare, leading to predicted exclusion in most lakes.Because interactions between fitness components within and between life stages vary among populations, these results show that local coexistence is population specific. Moreover, we show that multiple mechanisms do not necessarily increase competitor coexistence, as they can also combine to yield exclusion. Identifying coexistence mechanisms in other systems will require greater focus on determining contributions of different fitness components across the life cycle shaping competitor coexistence in a way that captures the potential for population‐level variation.