Evolutionary stability of coexistence due to the storage effect in a two-season model
Evolutionary stability of coexistence due to the storage effect in a two-season model
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DOI：
10.1007/s12080-016-0314-z
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发表时间：
2017-03-01
影响因子：
1.6
通讯作者：
Klausmeier, Christopher A.
中科院分区：
文献类型：
--
作者：
Miller, Elizabeth T.;Klausmeier, Christopher A.
自生态学创立以来，物种共存问题一直是生态学的核心问题。始终存在的环境变化可能是这个问题的一个答案。先前的模型已经证明，物种可以利用这种变异，通过不同的环境反应（储存效应）与竞争对手共存。然而，当控制物种环境反应的特征能够进化时，共存就无法保证。在这项研究中，我们使用连续时间、双季节模型来确定竞争物种在其季节性表现特征中的进化结果。我们扩展了竞争排斥原理，表明存储效应只能允许不超过 N 个物种在 N 个离散季节中共存，而没有相对非线性。我们发现了一个广阔的参数空间区域，其中共存在进化上是稳定的。该区域的大小取决于相对于个体寿命的波动周期。相对较长的周期波动会产生较大的共存区域，但随着周期的减小，该区域逐渐缩小并消失。最后，我们根据切森的均衡和稳定机制概念来运用自适应动力学技术，以证明短期共存的崩溃是由于环境与竞争之间的稳定协方差的丧失造成的。
The question of species coexistence has been central to ecology since its founding. Ever-present environmental variation may be one answer to that question. Previous models have demonstrated that species can exploit this variation to coexist with competitors by having different environmental responses (the storage effect). When traits governing species' environmental response can evolve, however, coexistence is not assured. In this study, we use a continuous time, twoseason model to determine the evolutionary outcome of competing species evolving in their seasonal performance trait. We extend the competitive exclusion principle to show that the storage effect can allow no more than N species to coexist on N discrete seasons with no relative nonlinearity. We find a broad region of parameter space where coexistence is evolutionarily stable. The size of this region depends on the period of fluctuations relative to the individual lifespan. Relatively long period fluctuations yield a large coexistence region, but as the period decreases, the region narrows and disappears asymptotically. Finally, we cast our adaptive dynamics technique in terms of Chesson's concept of equalizing and stabilizing mechanisms to demonstrate that the breakdown in coexistence at short periods is due to loss of the stabilizing covariance between the environment and competition.