Efficiency functionals for the Levy flight foraging hypothesis

We consider a forager diffusing via a fractional heat equation and we introduce several efficiency functionals whose optimality is discussed in relation to the Levy exponent of the evolution equation. Several biological scenarios, such as a target close to the forager, a sparse environment, a target located away from the forager and two targets are specifically taken into account. The optimal strategies of each of these configurations are here analyzed explicitly also with the aid of some special functions of classical flavor and the results are confronted with the existing paradigms of the Levy foraging hypothesis. Interestingly, one discovers bifurcation phenomena in which a sudden switch occurs between an optimal (but somehow unreliable) Levy foraging pattern of inverse square law type and a less ideal (but somehow more secure) classical Brownian motion strategy. Additionally, optimal foraging strategies can be detected in the vicinity of the Brownian one even in cases in which the Brownian one is pessimizing an efficiency functional.

Automated summary

This article discusses the optimality of several efficiency functionals in relation to the Levy exponent of a forager diffusing via a fractional heat equation. Different biological scenarios are considered and the results are compared with existing paradigms. Bifurcation phenomena are discovered, revealing a switch between optimal Levy foraging pattern and classical Brownian motion strategy.