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arXiv · 2509.16385

Parameter variability can produce heavy tails in a model for the spatial distribution of settling organisms

Luis F. Gordillo·Priscilla E. Greenwood
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Abstract

We show that a simple mechanistic model of spatial dispersal for settling organisms, subject to parameter variability, can generate heavy-tailed radial probability density functions. The movement of organisms in the model consists of a two-dimensional diffusion that ceases after a random time, where the parameters that characterize each of these stages have been randomized. Our findings show that these minimal assumptions can yield heavy-tailed dispersal patterns, providing a simplified framework that increases the understanding of long-distance dispersal events in movement ecology.

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Luis F. Gordillo, Priscilla E. Greenwood. 2025-09-19. Parameter variability can produce heavy tails in a model for the spatial distribution of settling organisms. https://arxiv.org/abs/2509.16385

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