| Autor: |
Potier S; Department of Biology, Lund University, Sölvegatan 35, Lund S-22362, Sweden.; Les Ailes de l'Urga, 72 rue de la vieille route, 27320 Marcilly la Campagne, France., Roulin A; Department of Ecology and Evolution, University of Lausanne, Biophore 1015, Switzerland., Martin GR; School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK., Portugal SJ; Department of Biological Science, School of Life and Environmental Sciences, Royal Holloway University of London, Egham, Surrey TW20 0EX, UK., Bonhomme V; ISEM, Univ Montpellier, CNRS, EPHE, IRD, 34095 Montpellier, France.; Équipe Dynamique de la biodiversité, anthropo-écologie, Place Eugène Bataillon - CC065, 34095 Montpellier Cedex 5, France., Bouchet T; Académie de Fauconnerie, SAS Puy du Fou France, 85500 Les Epesses, France., de Romans R; Espace Rambouillet, Office National des Forêts, route du coin du bois, 78120 Sonchamp, France., Meyrier E; Les Aigles du Léman, Domaine de Guidou, 74140 Sciez sur Léman, France., Kelber A; Department of Biology, Lund University, Sölvegatan 35, Lund S-22362, Sweden. |
| Abstrakt: |
The binocular field of vision differs widely in birds depending on ecological traits such as foraging. Owls (Strigiformes) have been considered to have a unique binocular field, but whether it is related to foraging has remained unknown. While taking into account allometry and phylogeny, we hypothesized that both daily activity cycle and diet determine the size and shape of the binocular field in owls. Here, we compared the binocular field configuration of 23 species of owls. While we found no effect of allometry and phylogeny, ecological traits strongly influence the binocular field shape and size. Binocular field shape of owls significantly differed from that of diurnal raptors. Among owls, binocular field shape was relatively conserved, but binocular field size differed among species depending on ecological traits, with larger binocular fields in species living in dense habitat and foraging on invertebrates. Our results suggest that (i) binocular field shape is associated with the time of foraging in the daily cycle (owls versus diurnal raptors) and (ii) that binocular field size differs between closely related owl species even though the general shape is conserved, possibly because the field of view is partially restricted by feathers, in a trade-off with auditory localization. |
