报告人： 孟雨 助理教授

报告题目： Impossible ecologies: interaction networks and stability of coexistence in ecological communities

时间： 2026年10月27日（周二）10:00—12:00

地点： 西安交通大学数学与统计学院2-3会议室

报告摘要：

Does an ecological community allow stable species coexistence? Approaches based on random matrix theory can describe the statistical effect of the proportions of competitive, mutualistic, and predator-prey interactions on stability. Still, identifying such general principles remains a central problem of systems ecology because such approaches cannot account for the full network arrangement of these interactions.

Here, we therefore develop a different approach: We analyse all interaction networks of 𝑁 ⩽ 5 species with Lotka–Volterra dynamics by combining exact results for 𝑁 ⩽ 3 species and numerical exploration. Surprisingly, we find that a very small subset of these networks are “impossible ecologies”, in which stable coexistence is non-trivially impossible. We prove that the possibility of stable coexistence in general ecologies is determined by similarly rare “irreducible ecologies”.

By statistical sampling, we show that the probability of stable coexistence varies over orders of magnitude even in ecologies that differ only in the network arrangement of identical interactions and analyse assembly of these ecological networks and evolutionary or environmental perturbations of them. Strikingly, this reveals that these network arrangements can influence stability of coexistence more than the proportions of interaction types. In this way, our approach of exhaustive analysis of small ecologies reveals the importance of the full structure of the network of interactions for stability of coexistence in ecological communities.

报告人简介：

孟雨，复旦大学智能复杂体系基础理论与关键技术实验室助理教授，毕业于英国阿伯丁大学，之后在德国马克斯·普朗克复杂系统物理研究所、德累斯顿系统生物学中心从事博士后研究，并任德国奥尔登堡大学助理研究员。

主要研究领域为数学生态学、复杂网络与非线性动力学，包括复杂生态系统中物种共存、生态网络结构与稳定性判定、网络动态演化与多层网络、多稳态系统的跃迁、生态临界现象预警与控制等方面的理论研究。研究成果发表于 Cell Systems、Journal of the Royal Society Interface、Physical Review E 和 Chaos 等期刊。