Abstract In this model, we considered the population density effect based on the evolutionary maintainable strategy (EMS) for optimal sex ratio strategy analysis, instead of the evolutionary stable strategy (ESS) under the population equilibrium. We used a cellular automaton model to simulate population dynamics using the birth-death process to monitor the effect of space structure on the optimal sex ratio in EMS.The simulation showed that when the whole population was a panmixia, the optimal sex ratio would be 1:1 (male/female), which conforms to the Fisher's theory prediction. However, in a structured population, the ratio favoured a female-bias sexratio, which conforms to the local mate competition theory prediction. With the decreased dispersal range, the sex ratio strategy tended towards a higher male proportion, which is similar to the local resource competition prediction.The predictions of our model partly conformed to classical theories and explained some gaps in the ESS model. However, the driving force differed from the classical sex ratio model.The sex ratio was selected by population fitness rather than mother's fitness. The optimal sex ratio strategy for a population is to guarantee mating success, indicating that population survival may provide a complementary explanation for the sex ratio evolution.

中文翻译：

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交配成功影响结构化人群的性别比例策略

摘要 在该模型中，我们考虑了基于进化维持策略（EMS）的种群密度效应进行最优性别比策略分析，而不是种群平衡下的进化稳定策略（ESS）。我们使用元胞自动机模型通过生死过程来模拟种群动态，以监测空间结构对EMS中最佳性别比的影响。 模拟表明，当整个种群为panmixia时，最佳性别比为1 :1（男/女），符合Fisher的理论预测。然而，在结构化的人群中，该比例偏向女性，这符合当地配偶竞争理论的预测。随着分散范围的减小，性别比例策略趋向于较高的男性比例，类似于局部资源竞争预测。我们模型的预测部分符合经典理论，并解释了ESS模型中的一些空白。然而，驱动力与经典的性别比例模型不同。性别比例是根据群体适应度而不是母亲的适应度来选择的。种群的最佳性别比例策略是保证交配成功，表明种群生存可能为性别比例演变提供补充解释。