A phase transition induces chaos in a predator-prey ecosystem with a dynamic fitness landscape
A phase transition induces chaos in a predator-prey ecosystem with a dynamic fitness landscape
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DOI：
10.1371/journal.pcbi.1005644
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发表时间：
2017-07-01
影响因子：
4.3
通讯作者：
Feldman, Marcus W.
中科院分区：
文献类型：
--
作者：
Gilpin, William;Feldman, Marcus W.
在许多生态系统中，自然选择可以迅速发生，足以影响种群动态，从而影响未来的选择。这表明，扩展经典的人口动态模型，包括这样的生态进化过程的重要性。在这里，我们描述了一个捕食-被捕食模型，其中猎物种群的增长依赖于猎物densitydependent健身景观。我们发现，这两个物种的生态系统是能够表现出混乱，即使在没有外部环境的变化或噪音，和混沌动力学的发病是可逆的适应景观之间的时代交替的结果稳定和破坏性的选择。我们在统计力学中的适应度函数和自由能之间进行类比，使我们能够使用一阶相变的物理理论来理解混沌捕食者-猎物动力学中快速循环的开始。我们使用定量技术来研究我们的模型的相关性，复杂的生态系统的观测研究，发现进化驱动的混沌动力学赋予社区的稳定性在“混乱的边缘”，同时创造了广泛分布的机会，在破坏性选择的时代，一个潜在的可观察到的签名混沌生态进化动力学的实验研究。
In many ecosystems, natural selection can occur quickly enough to influence the population dynamics and thus future selection. This suggests the importance of extending classical population dynamics models to include such eco-evolutionary processes. Here, we describe a predator-prey model in which the prey population growth depends on a prey densitydependent fitness landscape. We show that this two-species ecosystem is capable of exhibiting chaos even in the absence of external environmental variation or noise, and that the onset of chaotic dynamics is the result of the fitness landscape reversibly alternating between epochs of stabilizing and disruptive selection. We draw an analogy between the fitness function and the free energy in statistical mechanics, allowing us to use the physical theory of first-order phase transitions to understand the onset of rapid cycling in the chaotic predator-prey dynamics. We use quantitative techniques to study the relevance of our model to observational studies of complex ecosystems, finding that the evolution-driven chaotic dynamics confer community stability at the "edge of chaos" while creating a wide distribution of opportunities for speciation during epochs of disruptive selection-a potential observable signature of chaotic eco-evolutionary dynamics in experimental studies.