title: Prey from the eyes of predators: Color discriminability of aposematic and mimetic butterflies from an avian visual perspective.
abstract: Predation exerts strong selection on mimetic butterfly wing color patterns, which also serve other functions such as sexual selection. Therefore, specific selection pressures may affect the sexes and signal components differentially. We tested three predictions about the evolution of mimetic resemblance by comparing wing coloration of aposematic butterflies and their Batesian mimics: (a) females gain greater mimetic advantage than males and therefore are better mimics, (b) due to intersexual genetic correlations, sexually monomorphic mimics are better mimics than female-limited mimics, and (c) mimetic resemblance is better on the dorsal wing surface that is visible to predators in flight. Using a physiological model of avian color vision, we quantified mimetic resemblance from predators' perspective, which showed that female butterflies were better mimics than males. Mimetic resemblance in female-limited mimics was comparable to that in sexually monomorphic mimics, suggesting that intersexual genetic correlations did not constrain adaptive response to selection for female-limited mimicry. Mimetic resemblance on the ventral wing surface was better than that on the dorsal wing surface, implying stronger natural and sexual selection on ventral and dorsal surfaces, respectively. These results suggest that mimetic resemblance in butterfly mimicry rings has evolved under various selective pressures acting in a sex- and wing surface-specific manner.
authors.affiliation: National Center for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India. shiyu@u.nus.edu.|Department of Biological Sciences, National University of Singapore, Singapore. shiyu@u.nus.edu.
authors.forename: Shiyu
authors.initials: S
authors.lastname: Su
authors.affiliation: Department of Biological Sciences, National University of Singapore, Singapore.
authors.forename: Matthew
authors.initials: M
authors.lastname: Lim
authors.affiliation: National Center for Biological Sciences, Tata Institute of Fundamental Research, Bangalore, India. krushnamegh@ncbs.res.in.
authors.forename: Krushnamegh
authors.initials: K
authors.lastname: Kunte
mesh_terms: D000818:Animals; D005075:Biological Evolution; D000067558:Biological Mimicry; D001717:Birds / Q000502:physiology*; D002080:Butterflies / Q000235:genetics / Q000502:physiology*; D003116:Color; D055253:Color Vision; D005260:Female; D008297:Male; D011235:Predatory Behavior; D012641:Selection, Genetic; D012727:Sex Characteristics; D014921:Wings, Animal / Q000502:physiology*
keywords: Batesian mimicry; Oriental butterflies; Western Ghats; butterfly wing colors; sexual dimorphism; visual modeling