Am Nat. 2021 Oct;198(4):441-459. doi: 10.1086/715746. Epub 2021 Aug 18.
AbstractResource dynamics influence the contemporary ecology of consumer-resource mutualisms. Suites of resource traits, such as floral nectar components, also evolve in response to different selective pressures, changing the ecological dynamics of the interacting species at the evolutionary equilibrium. Here we explore the evolution of resource-provisioning traits in a biotically pollinated plant that produces nectar as a resource for beneficial consumers. We develop a mathematical model describing natural selection on two quantitative nectar traits: maximum nectar production rate and maximum nectar reservoir volume. We use this model to examine how nectar production dynamics evolve under different ecological conditions that impose varying cost-benefit regimes on resource provisioning. The model results predict that natural selection favors higher nectar production when ecological factors limit the plant or pollinator's abundance (e.g., a lower productivity environment or a higher pollinator conversion efficiency). We also find that nectar traits evolve as a suite in which higher costs of producing one trait select for a compensatory increase in investment in the other trait. This empirically explicit approach to studying the evolution of consumer-resource mutualisms illustrates how natural selection acting via direct and indirect pathways of species interactions generates patterns of resource provisioning seen in natural systems.
摘要
资源动态影响消费者-资源共生关系的当代生态学。资源特征的套件，如花卉花蜜成分，也会响应不同的选择压力而进化，从而改变相互作用物种在进化平衡中的生态动态。在这里，我们探索了一种生物授粉植物中资源供应特征的进化，该植物产生花蜜作为有益消费者的资源。我们开发了一个描述两个定量花蜜特征（最大花蜜产量和最大花蜜储存量）自然选择的数学模型。我们使用该模型来研究在不同的生态条件下，花蜜生产动态如何进化，这些生态条件对资源供应施加了不同的成本效益。模型结果预测，当生态因素限制植物或传粉者的丰度时（例如，生产力较低的环境或较高的传粉者转化效率），自然选择有利于更高的花蜜产量。我们还发现，花蜜特征作为一个套件进化，其中生产一种特征的成本较高会选择另一种特征的投资补偿性增加。这种通过物种相互作用的直接和间接途径来研究消费者-资源共生关系进化的实证方法说明了自然选择如何通过产生在自然系统中观察到的资源供应模式来发挥作用。
