Coexistence of two types on a single resource in discrete time
Coexistence of two types on a single resource in discrete time
复制标题
离散时间内单一资源上两种类型的共存
DOI：
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
F. Adler
中科院分区：
文献类型：
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作者：
F. Adler
Armstrong和麦基希（1980）已经证明，在连续时间中模拟的两个物种可以在一个资源上共存，只要其中一个物种自主振荡。本文在离散时间上证明了并行结果。我认为一个确定性模型的两个无性类型在一个单一的补丁竞争一个单一的资源，并表明，这样的系统一般产生振荡共存或双稳态，如果其中一个类型显示周期性或混沌行为隔离。共存或双稳态的条件来自描述健身作为资源可用性的函数的函数的凸性。我还分析了是否一个稳定的类型，一个类型的稳定平衡人口规模时，孤立地考虑，可以侵入一个不稳定类型的周期轨道，并表明，相同的凸性条件区分这两种情况。被广泛认为是指数或Ricker模型的人口动态位于两种情况之间的边界，在这种情况下是高度退化。
Armstrong and McGehee (1980) have shown that two species modeled in continuous time can coexist on a single resource provided that one species oscillates autonomously. This paper demonstrates the parallel result in discrete time. I consider a deterministic model of two asexual types in a single patch competing for a single resource, and show that such systems generically produce oscillatory coexistence or bistability if one of the types displays periodic or chaotic behavior in isolation. The conditions for coexistence or bistability are derived in terms of the convexity of the functions describing fitness as a function of resource availability. I also analyze whether or not a stable type, a type with a stable equilibrium population size when considered in isolation, can invade a periodic orbit of an unstable type, and show that the same convexity condition distinguishes these two cases. The widely considered exponential or Ricker model for population dynamics lies on the boundary between the two cases and is highly degenerate in this context.