休眠稳定非传递竞争动态
Dormancy stabilizes non-transitive competitive dynamics
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中文总结 AI 辅助
本研究构建种群遗传学框架，发现休眠可作为时间避难所，通过离散时间Wright-Fisher模型结合种子库与频率依赖相互作用，稳定非传递竞争系统，实现长期共存。
中文摘要 AI 辅助
竞争相互作用可维持多样性，但在充分混合的种群中，随机波动常导致灭绝，共存往往十分脆弱，非传递系统（如石头-剪刀-布动态）便是如此，这类系统中没有单一类型能在全局占据主导。虽然空间结构可通过提供空间避难所来稳定这些系统，但在充分混合的环境中，类似机制是否能在时间维度发挥作用仍不清楚。本文构建了一个种群遗传学框架，表明休眠可作为时间避难所，保存谱系并防止其在相互作用驱动的波动下固定（即某一类型占据全部种群）。我们引入了离散时间 Wright-Fisher 模型，该模型结合了广义种子库与频率依赖相互作用，允许个体从过去多代中抽样的潜在亲本处遗传自身类型。这一构建提供了一个易于处理的框架，其中休眠可储存并重新引入已丢失的类型。在弱选择或中等选择的情况下，我们对由此产生的类型频率过程证明了多维扩散极限，并利用它分析复杂的选择相互作用。在非传递系统中，休眠可稳定原本会因随机灭绝而崩溃的轨迹，延长固定时间并维持共存。这些效应无法仅通过有效种群大小的增加来解释。我们的结果表明，休眠引入了时间记忆，从根本上改变了竞争动态，稳定了原本脆弱的系统并实现了长期共存。
英文摘要
Competitive interactions can maintain diversity, yet coexistence is often fragile in well-mixed populations, where stochastic fluctuations can lead to extinction. This is the case in non-transitive systems, such as rock-paper-scissors dynamics, where no single type dominates globally. While spatial structure can stabilize these systems by providing refuges in space, it remains unclear whether analogous mechanisms can operate in time in well-mixed environments. Here, we develop a population-genetic framework showing that dormancy can act as a temporal refuge, preserving lineages and preventing collapse to fixation under interaction-driven fluctuations. We introduce a discrete-time Wright-Fisher model that combines generalized seed-banks with frequency-dependent interactions, allowing individuals to inherit their type from potential parents sampled across multiple past generations. This construction provides a tractable framework in which dormancy stores and later reintroduces lost types. In the case of either weak or moderate selection, we prove a multidimensional diffusion limit for the resulting type-frequency process and use it to analyze complex selective interactions. In non-transitive systems, dormancy stabilizes trajectories that would otherwise collapse through stochastic extinction, extends fixation times, and sustains coexistence. These effects cannot be explained solely by an increase in effective population size. Our results show that dormancy introduces temporal memory that qualitatively alters competitive dynamics, stabilizing otherwise fragile systems and enabling long-term coexistence.
