title: Path integration mediated systematic search: a Bayesian model.
abstract: The systematic search behaviour is a backup system that increases the chances of desert ants finding their nest entrance after foraging when the path integrator has failed to guide them home accurately enough. Here we present a mathematical model of the systematic search that is based on extensive behavioural studies in North African desert ants Cataglyphis fortis. First, a simple search heuristic utilising Bayesian inference and a probability density function is developed. This model, which optimises the short-term nest detection probability, is then compared to three simpler search heuristics and to recorded search patterns of Cataglyphis ants. To compare the different searches a method to quantify search efficiency is established as well as an estimate of the error rate in the ants' path integrator. We demonstrate that the Bayesian search heuristic is able to automatically adapt to increasing levels of positional uncertainty to produce broader search patterns, just as desert ants do, and that it outperforms the three other search heuristics tested. The searches produced by it are also arguably the most similar in appearance to the ant's searches.
authors.affiliation: AgResearch Ltd, Lincoln Research Centre, Cnr Springs Road and Gerald Street, Private Bag 4749, Christchurch 8140, New Zealand. robert.vickerstaff@gmail.com
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Vickerstaff
authors.forename: Tobias
authors.initials: T
authors.lastname: Merkle
mesh_terms: D000818:Animals; D001000:Ants / Q000502:physiology*; D001070:Appetitive Behavior / Q000502:physiology; D001499:Bayes Theorem; D003889:Desert Climate; D006702:Homing Behavior / Q000502:physiology*; D008954:Models, Biological; D013997:Time Factors