Emergence of a Novel Phase in Population and Community Dynamics Due to Fat-Tailed Environmental Correlations

Immanuel Meyer; Ami Taitelbaum; Michael Assaf; Nadav M. Shnerb

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arXiv · 2311.08825

Emergence of a Novel Phase in Population and Community Dynamics Due to Fat-Tailed Environmental Correlations

Immanuel Meyer·Ami Taitelbaum·Michael Assaf·Nadav M. Shnerb

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Abstract

Temporal environmental noise (EN) is a prevalent natural phenomenon that controls population and community dynamics, shaping the destiny of biological species and genetic types. Conventional theoretical models often depict EN as a Markovian process with an exponential distribution of correlation times, resulting in two distinct qualitative dynamical categories: quenched (pertaining to short demographic timescales) and annealed (pertaining to long timescales). However, numerous empirical studies demonstrate a fat-tailed decay of correlation times. Here, we study the consequences of power-law correlated EN on the dynamics of isolated and competing populations. We reveal the emergence of a novel intermediate phase that lies between the quenched and annealed regimes. Within this phase, dynamics are primarily driven by rare, yet not exceedingly rare, long periods of almost-steady environmental conditions. For an isolated population, the time to extinction in this phase exhibits a novel scaling with the abundance, and also a non-monotonic dependence on the spectral exponent.

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Immanuel Meyer, Ami Taitelbaum, Michael Assaf, Nadav M. Shnerb. 2023-11-15. Emergence of a Novel Phase in Population and Community Dynamics Due to Fat-Tailed Environmental Correlations. https://arxiv.org/abs/2311.08825

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