Shu Hongying, Hu Xi, Wang Lin, Watmough James
Department of Mathematics, Tongji University, Shanghai, 200092, P. R. China.
Department of Mathematics and Statistics, University of New Brunswick, Fredericton, E3B 5A3, Canada.
J Math Biol. 2015 Dec;71(6-7):1269-98. doi: 10.1007/s00285-015-0857-4. Epub 2015 Feb 6.
In many predator-prey models, delay has a destabilizing effect and induces oscillations; while in many competition models, delay does not induce oscillations. By analyzing a rather simple delayed intraguild predation model, which combines both the predator-prey relation and competition, we show that delay in intraguild predation models promotes very complex dynamics. The delay can induce stability switches exhibiting a destabilizing role as well as a stabilizing role. It is shown that three types of bistability are possible: one stable equilibrium coexists with another stable equilibrium (node-node bistability); one stable equilibrium coexists with a stable periodic solution (node-cycle bistability); one stable periodic solution coexists with another stable periodic solution (cycle-cycle bistability). Numerical simulations suggest that delay can also induce chaos in intraguild predation models.
在许多捕食者 - 猎物模型中,延迟具有破坏稳定性的作用并引发振荡;而在许多竞争模型中,延迟并不会引发振荡。通过分析一个相当简单的延迟种内捕食模型,该模型结合了捕食者 - 猎物关系和竞争关系,我们表明种内捕食模型中的延迟会促进非常复杂的动态变化。延迟能够引发稳定性切换,既表现出破坏稳定性的作用,也表现出稳定作用。结果表明可能存在三种双稳性:一个稳定平衡点与另一个稳定平衡点共存(节点 - 节点双稳性);一个稳定平衡点与一个稳定周期解共存(节点 - 周期双稳性);一个稳定周期解与另一个稳定周期解共存(周期 - 周期双稳性)。数值模拟表明,延迟也能在种内捕食模型中引发混沌。