Sector fidelity--an advantageous foraging behavior resulting from a heuristic search strategy

The desert ant Cataglyphis exhibits a strong tendency toward returning to its previous foraging direction when the last foraging run was successful. This behavior is called sector fidelity. A very simple behavioral rule, the τ-rule, has previously been identified as the possible underlying mechanism. Up to now, sector fidelity has been considered a means of facilitating navigation by exploiting familiar landmark information. We propose that sector fidelity enhances the foraging success of ants or other animals in an environment with a heterogeneous resource distribution. We tested the τ-rule and another promising behavioral rule in a very simple environment and modeled the foraging success of these strategies. For each condition, the parameters of the 2 heuristics were optimized using an evolutionary algorithm. The results of our simulations show that the τ-rule performs very well under different resource distributions and availabilities. It can therefore function as a very general adaptive foraging strategy for finding prey in landscapes with heterogeneous resource distributions. Copyright 2008, Oxford University Press.