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bioRxiv · 10.64898/2026.01.12.698984

The topology of ecological drift

Kalirad, A.·Sommer, R. J.
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Abstract

Ecological drift, the random fluctuation of abundance in communities, can drastically affect the possibility of coexistence. However, ecological drift has mostly been considered at the macro-ecological scale, whereas its potential contribution to short-term ecological dynamics remains underexplored. Here, we propose a stage-structured ecological graph theory (ssEcoGT) to include complex life cycles and multiple ecological interactions to study the topology of ecological drift. ssEcoGT enables rigorous exploration of how topology of a community can affect the possibility of coexistence between two species. Using ssEcoGT, it is possible to compare the behavior of a range of models - e.g., random graphs, random graphs with intraguild predation, and random graphs with rewiring - against a complete graph of the same size. Thus, ssEcoGT provides a new tool to explore the interplay between ecological drift, competition, and stage-specific interactions.

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Kalirad, A., Sommer, R. J.. 2026-01-13. The topology of ecological drift. https://doi.org/10.64898/2026.01.12.698984

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