title: How the zebra got its stripes: a problem with too many solutions.
abstract: The adaptive significance of zebra stripes has thus far eluded understanding. Many explanations have been suggested, including social cohesion, thermoregulation, predation evasion and avoidance of biting flies. Identifying the associations between phenotypic and environmental factors is essential for testing these hypotheses and substantiating existing experimental evidence. Plains zebra striping pattern varies regionally, from heavy black and white striping over the entire body in some areas to reduced stripe coverage with thinner and lighter stripes in others. We examined how well 29 environmental variables predict the variation in stripe characteristics of plains zebra across their range in Africa. In contrast to recent findings, we found no evidence that striping may have evolved to escape predators or avoid biting flies. Instead, we found that temperature successfully predicts a substantial amount of the stripe pattern variation observed in plains zebra. As this association between striping and temperature may be indicative of multiple biological processes, we suggest that the selective agents driving zebra striping are probably multifarious and complex.
authors.affiliation: Department of Ecology and Evolutionary Biology , University of California, 610 Charles E. Young Drive South , Los Angeles, CA 90095, USA ; Center for Tropical Research, Institute of the Environment and Sustainability , University of California, 619 Charles E. Young Drive East , Los Angeles, CA 90095, USA.
authors.forename: Brenda
authors.initials: B
authors.lastname: Larison
authors.affiliation: Department of Ecology and Evolutionary Biology , University of California, 610 Charles E. Young Drive South , Los Angeles, CA 90095, USA ; Center for Tropical Research, Institute of the Environment and Sustainability , University of California, 619 Charles E. Young Drive East , Los Angeles, CA 90095, USA.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Harrigan
authors.affiliation: Institute for Evolution and Ecology , University of Tübingen, Building E, Floor 4, Auf der Morgenstelle 28 , Tübingen 72076, Germany.
authors.forename: Henri A
authors.initials: HA
authors.lastname: Thomassen
authors.affiliation: Department of Ecology and Evolutionary Biology , Princeton University, 106A Guyot Hall , Princeton, NJ 08544, USA.
authors.forename: Daniel I
authors.initials: DI
authors.lastname: Rubenstein
authors.affiliation: Department of Mathematics , University of California, 520 Portola Plaza, Math Sciences Building 6363 , Los Angeles, CA 90095, USA.
authors.forename: Alec M
authors.initials: AM
authors.lastname: Chan-Golston
authors.affiliation: Department of Mathematics , University of California, 520 Portola Plaza, Math Sciences Building 6363 , Los Angeles, CA 90095, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Li
authors.affiliation: Department of Ecology and Evolutionary Biology , University of California, 610 Charles E. Young Drive South , Los Angeles, CA 90095, USA ; Center for Tropical Research, Institute of the Environment and Sustainability , University of California, 619 Charles E. Young Drive East , Los Angeles, CA 90095, USA.
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Smith
keywords: ecological predictions; patterning; random forest; species distribution modelling; stripes; zebra