Evolutionary suicide and evolution of dispersal in structured metapopulations
Evolutionary suicide and evolution of dispersal in structured metapopulations
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DOI：
10.1007/s002850200151
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发表时间：
2002-08-01
影响因子：
1.9
通讯作者：
Dieckmann, U
中科院分区：
文献类型：
--
作者：
Gyllenberg, M;Parvinen, K;Dieckmann, U
研究了一类结构集合种群模型中扩散的演化。集合种群由大量（无限）生活在可居住环境中的当地种群组成。斑块之间的扩散是仿照扩散池和个人在斑块之间的运输暴露于死亡的风险。偶尔，局部的灾难会消灭当地的种群：受影响的斑块中的所有个体都会死亡，但斑块仍然适合居住。我们证明，在没有灾难的情况下，不迁移的策略是进化稳定的。在一组给定的环境条件下，集合种群可能是可行的，但选择可能有利于推动集合种群灭绝的扩散率。这种现象被称为进化自杀。我们表明，在我们的模型中，进化自杀可以发生的灾难率，随着当地人口规模的减少而增加。如果斑块内的局部增长表现出Allee效应，那么在恒定的灾难率下也会发生进化自杀。我们研究了进化自杀的进化分叉，并表明不连续的灭绝过渡是进化自杀发生的必要条件。换句话说，如果种群规模在参数空间中的生存边界处平滑地接近于零，则该边界是进化排斥的，并且不会发生自杀。
We study the evolution of dispersal in a structured metapopulation model. The metapopulation consists of a large (infinite) number of local populations living in patches of habitable environment. Dispersal between patches is modelled by a disperser pool and individuals in transit between patches are exposed to a risk of mortality. Occasionally, local catastrophes eradicate a local population: all individuals in the affected patch die, yet the patch remains habitable. We prove that, in the absence of catastrophes, the strategy not to migrate is evolutionarily stable. Under a given set of environmental conditions, a metapopulation may be viable and yet selection may favor dispersal rates that drive the metapopulation to extinction. This phenomenon is known as evolutionary suicide. We show that in our model evolutionary suicide can occur for catastrophe rates that increase with decreasing local population size. Evolutionary suicide can also happen for constant catastrophe rates, if local growth within patches shows an Allee effect. We study the evolutionary bifurcation towards evolutionary suicide and show that a discontinuous transition to extinction is a necessary condition for evolutionary suicide to occur. In other words, if population size smoothly approaches zero at a boundary of viability in parameter space, this boundary is evolutionarily repelling and no suicide can occur.