Year: 2026
Type: article
Abstract: Diffusion models are widely used to describe insect dispersal, but their validity depends on the time and length scales over which movement is observed. Motion can only be approximated as random at long length scales, in which the combined effects of many non-random processes become indistinguishable. In this study, simple random walk (SRW) and correlated random walk (CRW) simulations examine how directional persistence affects effective diffusion in five insect test-cases derived from literature. For each case, the simulated x-marginal endpoint distributions from both models were compared with Gaussian diffusion distributions calculated from literature reported diffusion coefficients. Agreement between the simulated and literature-based distributions was quantified using the Kolmogorov Smirnov distance (KSD). The CRW model produced closer agreement with the literature-based distributions than the SRW model, indicating that directional persistence improved the representation of effective dispersal. The heading angle time series was then analyzed by examining how its variation was distributed across frequencies. Directional persistence increased low frequency heading structure and reduced rapid heading fluctuations. A characteristic frequency was identified from this frequency based analysis and converted into characteristic time and length scales. At scales substantially longer than these characteristic scales, the simulated motion is expected to be better approximated by an effective diffusion description. We believe that these tools provide new ways to conceptualize diffusive models, and may provide a link between diffusive (continuous) and agent-based techniques.
Source: Ecological Modelling
Language: English
Field: Medicine
Domain: Health Sciences
Open Access status: hybrid
Estimated APC paid: $2,810
Award: G814497173
OpenAlex ID: W7164505592