Publications

The development of ecological systems along paths of least resistance

Jie Deng, Otto X. Cordero, Tadashi Fukami, Simon A. Levin, Robert M. Pringle, Ricard Solé, Serguei Saavedra

Current Biology, 2024

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Short summary: Using a probabilistic framework grounded in the Lotka-Volterra model and Markov chains, we theoretically show that the developmental path from fast- to slow-growing species is most likely to emerge as species minimize environmental resistance to enhance their survival. Additionally, our findings indicate that sequential development (where species appear one by one) is more likely to succeed than simultaneous development (where all species appear at once). We support our theory with empirical data spanning a diverse range of organisms and ecosystems—from microbes to plants to animals.

Short summary: We study the limits to invasion prediction using coexistence outcomes under a geometric and probabilistic Lotka-Volterra framework. We show that while survival probability in coexistence dynamics can be fairly closely translated into colonization probability in invasion dynamics, the translation is less precise between community persistence and community augmentation, and worse between exclusion probability and replacement probability.

Short summary: We study the probability of pairwise coexistence within multispecies systems governed by Lotka-Volterra dynamics from a geometric and systems perspective. We derive analytically and numerically system-level indicators of long-term and short-term (transient) pairwise coexistence within multispecies systems, respectively. Using the experimental data of fruit fly gut microbiota, we illustrate how our system-level indicators can be applied to understand long-term and short-term effects of the gut microbiota on the coexistence of each pair of bacteria.

Short summary: We integrate tractable theoretical systems with tractable experimental systems to find general conditions under which non-resident species can change the collection of resident communities by either promoting or suppressing resident species—"game-changing species". We study the generalization of game-changing species under controlled and changing conditions using the experimental data of in vitro (soil) and in vivo (gut) microbial communities, respectively. Despite the strong context-dependency, our work shows that it is possible to unveil regularities shaping changes in the species collection of microbial communities.