Bet-hedging is a phenotype diversification strategy that combines a fast-growing vulnerable phenotype with a slow-growing resistant phenotype. In environments switching between favorable and unfavorable conditions, bet-hedging optimizes growth and reduces fluctuations over a long time, which is expected to reduce extinction risk. Here, we address directly how bet-hedging can reduce extinction probability in an agent-based model. An agent-based model is appropriate for studying extinction due to the low number of individuals close to extinction. We also show that the agent-based model converges to the collective model behavior for populations of $100$ individuals or more. However, the collective model provides relevant qualitative insight even for low populations. The collective model provides expressions for extinction that stress the relevance of the population number, showing that a factor four increase in the total population has a greater effect than a change of strategy from maximum growth to minimal extinction. This work provides further insight into the impact of finite population effects on the bet-hedging strategy's success.
Evolutionary adaptation through bet-hedging in finite populations under fluctuating environments
Grupo Interdisciplinar de Sistemas Complejos (GISC) and Departamento de Estructura de la Materia, Física Térmica y Electrónica, Universidad Complutense de Madrid（马德里康普顿斯大学复杂系统跨学科小组及物质结构、热学与电子学系）
Seasonality can induce coexistence of multiple bet-hedging strategies in Dictyostelium discoideum via storage effect
D. discoideum最近被认为是赌注对冲的一个例子。在饥饿时，单细胞变形虫的种群在聚集体和非聚集体之间分裂，聚集体形成由柄和抗性孢子组成的子实体。长时间的饥饿有利于孢子，但营养细胞可以在快速恢复的环境中利用资源。这种划分可以被理解为一种赌注对冲策略，它会随着随机饥饿时间的变化而变化。基因型由每种类型细胞之间的不同平衡来定义。在这个框架中，如果生态条件是根据平均饥饿时间（即饥饿开始和新的食物脉冲到达之间的时间）来定义的，则单个基因型在每个环境中占主导地位，这与自然界中观察到的巨大的遗传多样性〈动〉<动>不一致。我们调查是否季节性，平均饥饿时间的周期性交替，允许共存的几种策略。我们使用非空间（混合良好）环境，不同菌株竞争资源脉冲。我们发现，季节性，我们通过两个季节模型，诱导的时间存储效应，可以促进多个基因型的稳定共存。需要满足两个条件。首先，饥饿时间在每个季节的分布不能重叠，以创造两个分化良好的栖息地在一年内。第二，在每个季节中必须发生许多生长-饥饿循环，以使适应良好的菌株生长并在随后的不利时期存活下来。生活史性状之间的额外权衡可以扩大共存的范围，增加共存策略的数量，有助于解释在D. discoideum
