title: Spectral information as an orientation cue in dung beetles.
abstract: During the day, a non-uniform distribution of long and short wavelength light generates a colour gradient across the sky. This gradient could be used as a compass cue, particularly by animals such as dung beetles that rely primarily on celestial cues for orientation. Here, we tested if dung beetles can use spectral cues for orientation by presenting them with monochromatic (green and UV) light spots in an indoor arena. Beetles kept their original bearing when presented with a single light cue, green or UV, or when presented with both light cues set 180° apart. When either the UV or the green light was turned off after the beetles had set their bearing in the presence of both cues, they were still able to maintain their original bearing to the remaining light. However, if the beetles were presented with two identical green light spots set 180° apart, their ability to maintain their original bearing was impaired. In summary, our data show that ball-rolling beetles could potentially use the celestial chromatic gradient as a reference for orientation.
authors.affiliation: Vision Group, Department of Biology, Lund University, 223 62 Lund, Sweden basil.el_jundi@biol.lu.se.
authors.forename: Basil
authors.initials: B
authors.lastname: El Jundi
authors.affiliation: Vision Group, Department of Biology, Lund University, 223 62 Lund, Sweden.
authors.forename: James J
authors.initials: JJ
authors.lastname: Foster
authors.affiliation: School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Wits 2050, South Africa.
authors.forename: Marcus J
authors.initials: MJ
authors.lastname: Byrne
authors.affiliation: Vision Group, Department of Biology, Lund University, 223 62 Lund, Sweden.
authors.forename: Emily
authors.initials: E
authors.lastname: Baird
authors.affiliation: Vision Group, Department of Biology, Lund University, 223 62 Lund, Sweden School of Animal, Plant and Environmental Sciences, University of the Witwatersrand, Wits 2050, South Africa.
authors.forename: Marie
authors.initials: M
authors.lastname: Dacke
mesh_terms: D000818:Animals; D001517:Coleoptera / Q000502:physiology* / Q000528:radiation effects; D003463:Cues; D008027:Light; D009949:Orientation; D014466:Ultraviolet Rays
keywords: chromatic contrast; colour vision; compass; insect; navigation