title: Vector-based and landmark-guided navigation in desert ants inhabiting landmark-free and landmark-rich environments.
abstract: Two species of desert ants - the North African Cataglyphis fortis and the central Australian Melophorus bagoti - differ markedly in the visual complexity of their natural habitats: featureless salt pans and cluttered, steppe-like terrain, respectively. Here we ask whether the two species differ in their navigational repertoires, in particular, whether in homing they place different emphasis on their vector-based and landmark-based routines. In trying to answer this question, we applied the same experimental paradigms to individual foragers of either species on either continent: training and/or testing with and/or without artificial landmark arrays. We found that the open-terrain species C. fortis runs off its (path integration) home vector much more readily even in unfamiliar landmark settings than the cluttered-terrain species M. bagoti. These data support the hypothesis that C. fortis has a higher propensity to rely on vector-mediated navigation, whereas in the same experimental situations M. bagoti more easily switches to landmark-guided behaviour. In the actual navigational performances, such species-specific propensities are most likely shaped by environment-dependent individual experiences.
authors.affiliation: Brain Research Institute, University of Zürich, Winterthurerstrasse 190, CH-8057, Zürich, Switzerland.
authors.forename: Cornelia
authors.initials: C
authors.lastname: Bühlmann
authors.forename: Ken
authors.initials: K
authors.lastname: Cheng
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Wehner
mesh_terms: D000818:Animals; D001000:Ants / Q000502:physiology*; D001315:Australia; D003463:Cues; D003889:Desert Climate; D006702:Homing Behavior; D009949:Orientation