title: Variation in cyanogenic compounds concentration within a Heliconius butterfly community: does mimicry explain everything?
abstract: Aposematic species advertise their unpalatability using warning signals such as striking coloration. Given that predators need to sample aposematic prey to learn that they are unprofitable, prey with similar warning signals share the cost of predator learning. This reduction in predation risk drives evolutionary convergence of warning signals among chemically defended prey (Müllerian mimicry). Whether such warning signal convergence is associated to similar defence levels among co-mimics is still an open question that has rarely been tested in wild populations. We quantified variation in cyanide-based (CN) chemical protection in wild caught individuals of eight aposematic Heliconius butterfly species belonging to four sympatric mimicry rings. We then tested for correlations between chemical protection and ecological species-specific traits.
  
  
  
  We report significant differences in CN concentrations both within and between sympatric species, even when accounting for the phylogeny, and within and between mimicry rings, even after considering inter-specific variation. We found significant correlations between CN concentration and both hostplant specialization and gregarious behaviour in adults and larvae. However, differences in CN concentrations were not significantly linked to mimicry ring abundance, although the two most toxic species did belong to the rarest mimicry ring.
  
  
  
  Our results suggest that mimicry can explain the variation in the levels of chemical defence to a certain extent, although other ecological factors are also relevant to the evolution of such variability.
authors.affiliation: Institut Systématique, Evolution, Biodiversité, UMR 7205 MNHN-CNRS-EPHE-UPMC- Sorbonne Universités, Muséum National d'Histoire Naturelle, Bâtiment d'entomologie, CP050, 57 rue Cuvier, 75005, Paris, France. moarias@gmail.com.
authors.forename: Mónica
authors.identifier: 0000-0003-1331-2604
authors.initials: M
authors.lastname: Arias
authors.affiliation: Institut Systématique, Evolution, Biodiversité, UMR 7205 MNHN-CNRS-EPHE-UPMC- Sorbonne Universités, Muséum National d'Histoire Naturelle, Bâtiment d'entomologie, CP050, 57 rue Cuvier, 75005, Paris, France.|Unité Molécules de Communication et Adaptation des Micro-organismes, UMR 7245 MNHN-CNRS, Sorbonne Universités, Muséum National d'Histoire Naturelle and CNRS, 57 rue Cuvier, CP 54, 75005, Paris, France.
authors.forename: Aimilia
authors.initials: A
authors.lastname: Meichanetzoglou
authors.affiliation: Institut Systématique, Evolution, Biodiversité, UMR 7205 MNHN-CNRS-EPHE-UPMC- Sorbonne Universités, Muséum National d'Histoire Naturelle, Bâtiment d'entomologie, CP050, 57 rue Cuvier, 75005, Paris, France.
authors.forename: Marianne
authors.initials: M
authors.lastname: Elias
authors.affiliation: Department of Biology, University of York, Heslington, York, YO10 5DD, UK.
authors.forename: Neil
authors.initials: N
authors.lastname: Rosser
authors.affiliation: Institut Systématique, Evolution, Biodiversité, UMR 7205 MNHN-CNRS-EPHE-UPMC- Sorbonne Universités, Muséum National d'Histoire Naturelle, Bâtiment d'entomologie, CP050, 57 rue Cuvier, 75005, Paris, France.
authors.forename: Donna Lisa
authors.initials: DL
authors.lastname: de-Silva
authors.affiliation: Unité Molécules de Communication et Adaptation des Micro-organismes, UMR 7245 MNHN-CNRS, Sorbonne Universités, Muséum National d'Histoire Naturelle and CNRS, 57 rue Cuvier, CP 54, 75005, Paris, France.
authors.forename: Bastien
authors.initials: B
authors.lastname: Nay
authors.affiliation: Institut Systématique, Evolution, Biodiversité, UMR 7205 MNHN-CNRS-EPHE-UPMC- Sorbonne Universités, Muséum National d'Histoire Naturelle, Bâtiment d'entomologie, CP050, 57 rue Cuvier, 75005, Paris, France.
authors.forename: Violaine
authors.initials: V
authors.lastname: Llaurens
mesh_terms: D000818:Animals; D005075:Biological Evolution; D000067558:Biological Mimicry; D002080:Butterflies / Q000737:chemistry / Q000502:physiology; D003486:Cyanides / Q000032:analysis* / Q000633:toxicity; D005260:Female; D007858:Learning; D008297:Male; D008954:Models, Biological; D011235:Predatory Behavior; D013045:Species Specificity
chemical_list: D003486:Cyanides