In this paper, we develop a single species evolutionary model with a continuous phenotypic trait in a pulsed pollution discharge environment and discuss the effects of pollution on the individual size of the species. The invasion fitness function of a monomorphic species is given, which involves the long-term average exponential growth rate of the species. Then the critical function analysis method is used to obtain the evolutionary dynamics of the system, which is related to interspecific competition intensity between mutant species and resident species and the curvature of the trade-off between individual size and the intrinsic growth rate. We conclude that the pollution affects the evolutionary traits and evolutionary dynamics. The worsening of the pollution can lead to rapid stable evolution toward a smaller individual size, while the opposite is more likely to generate evolutionary branching and promote species diversity. The adaptive dynamics of coevolution of dimorphic species is further analyzed when evolutionary branching occurs.

中文翻译：

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污染对单一物种个体大小的影响

在本文中，我们开发了一个在脉冲排污环境中具有连续表型特征的单一物种进化模型，并讨论了污染对物种个体大小的影响。给出了单态物种的入侵适应度函数，该函数涉及该物种的长期平均指数增长率。然后用临界函数分析法得到系统的进化动力学，它与突变物种和常驻物种之间的种间竞争强度以及个体大小和内在增长率之间的权衡曲率有关。我们得出结论，污染影响进化特征和进化动力学。污染的恶化会导致快速稳定地向更小的个体进化，而相反的更有可能产生进化分支并促进物种多样性。当进化分支发生时，进一步分析了二态物种共同进化的适应性动力学。