Data from: Asymmetric competition impacts evolutionary rescue in a changing environment

How interspecific competition influences evolution in response to abiotic change is key to predicting the impact of climate change. Previous work has shown that, when two species compete for a directionally shifting resource abundance distribution in time, the species lagging behind the resource peak is the first to go extinct due to competitive exclusion. However, this work assumed symmetrically distributed resources and competition. Asymmetries can generate differences between species in population sizes, genetic variation, and trait means. We show that asymmetric resource availability or competition can facilitate coexistence and even occasionally cause the leading species to go extinct first. Surprisingly, we also find cases where traits evolve in the opposite direction to the changing environment because of a "vacuum of competitive release'' created when the lagging species declines in number. Thus, the species exhibiting the slowest rate of trait evolution is not always the most likely to go extinct in a changing environment.种间竞争（interspecific competition）如何调控生物响应非生物环境变化（abiotic change）的演化进程，是预判气候变化（climate change）影响的核心科学议题。既往研究证实，当两个物种争夺随时间发生方向性偏移的资源丰度分布时，滞后于资源峰值的物种会因竞争排除（competitive exclusion）率先走向灭绝。但此类研究均假设资源分布与种间竞争均为对称模式；而不对称性可引发不同物种在种群规模、遗传变异（genetic variation）与性状均值（trait means）层面产生差异。本研究表明，不对称的资源可获得性或种间竞争不仅能够促进物种共存（coexistence），甚至偶尔会使处于资源峰值领先地位的物种率先灭绝。尤为意外的是，我们还观测到部分场景中，由于滞后物种种群数量衰减所催生的"竞争释放真空（vacuum of competitive release）"，物种性状演化方向会与环境变化方向相悖。由此可见，在环境变化的背景下，性状演化速率最慢的物种并非始终是最易灭绝的类群。