title: The function of zebra stripes.
abstract: Despite over a century of interest, the function of zebra stripes has never been examined systematically. Here we match variation in striping of equid species and subspecies to geographic range overlap of environmental variables in multifactor models controlling for phylogeny to simultaneously test the five major explanations for this infamous colouration. For subspecies, there are significant associations between our proxy for tabanid biting fly annoyance and most striping measures (facial and neck stripe number, flank and rump striping, leg stripe intensity and shadow striping), and between belly stripe number and tsetse fly distribution, several of which are replicated at the species level. Conversely, there is no consistent support for camouflage, predator avoidance, heat management or social interaction hypotheses. Susceptibility to ectoparasite attack is discussed in relation to short coat hair, disease transmission and blood loss. A solution to the riddle of zebra stripes, discussed by Wallace and Darwin, is at hand.
authors.affiliation: 1] Department of Wildlife, Fish and Conservation Biology, University of California at Davis, 1 Shields Avenue, Davis, California 95616, USA [2] Center for Population Biology, University of California at Davis, 1 Shields Avenue, Davis, California 95616, USA.
authors.forename: Tim
authors.initials: T
authors.lastname: Caro
authors.affiliation: Department of Wildlife, Fish and Conservation Biology, University of California at Davis, 1 Shields Avenue, Davis, California 95616, USA.
authors.forename: Amanda
authors.initials: A
authors.lastname: Izzo
authors.affiliation: 1] Department of Entomology, University of California at Davis, 1 Shields Avenue, Davis, California 95616, USA [2] Fogarty International Center, National Institutes of Health, 31 Center Drive, MSC 2220, Bethesda, Maryland 20892, USA.
authors.forename: Robert C
authors.initials: RC
authors.lastname: Reiner
authors.affiliation: Department of Wildlife, Fish and Conservation Biology, University of California at Davis, 1 Shields Avenue, Davis, California 95616, USA.
authors.forename: Hannah
authors.initials: H
authors.lastname: Walker
authors.affiliation: Department of Biological Sciences, California State University, Long Beach, 1250 Bellflower Boulevard, Long Beach, California 90840, USA.
authors.forename: Theodore
authors.initials: T
authors.lastname: Stankowich
mesh_terms: D000818:Animals; D005075:Biological Evolution; D018397:Equidae / Q000033:anatomy & histology / Q000145:classification / Q000235:genetics* / Q000502:physiology; D010802:Phylogeny