TY - JOUR

T1 - Variation of chemical compounds in wild Heliconiini reveals ecological factors involved in the evolution of chemical defenses in mimetic butterflies

AU - Sculfort, Ombeline

AU - de Castro, Erika C. P.

AU - Kozak, Krzysztof M.

AU - Bak, Søren

AU - Elias, Marianne

AU - Nay, Bastien

AU - Llaurens, Violaine

PY - 2020

Y1 - 2020

N2 - Evolutionary convergence of color pattern in mimetic species is tightly linked with the evolution of chemical defenses. Yet, the evolutionary forces involved in natural variations of chemical defenses in aposematic species are still understudied. Herein, we focus on the evolution of chemical defenses in the butterfly tribe Heliconiini. These neotropical butterflies contain large concentrations of cyanogenic glucosides, cyanide-releasing compounds acting as predator deterrent. These compounds are either de novo synthesized or sequestered from their Passiflora host plant, so that their concentrations may depend on host plant specialization and host plant availability. We sampled 375 wild Heliconiini butterflies across Central and South America, covering 43% species of this clade, and quantify individual variations in the different CGs using liquid chromatography coupled with tandem mass spectrometry. We detected new compounds and important variations in chemical defenses both within and among species. Based on the most recent and well-studied phylogeny of Heliconiini, we show that ecological factors such as mimetic interactions and host plant specialization have a significant association with chemical profiles, but these effects are largely explained by phylogenetic relationships. Our results therefore suggest that shared ancestries largely contribute to chemical defense variation, pointing out at the interaction between historical and ecological factors in the evolution of Mullerian mimicry.

AB - Evolutionary convergence of color pattern in mimetic species is tightly linked with the evolution of chemical defenses. Yet, the evolutionary forces involved in natural variations of chemical defenses in aposematic species are still understudied. Herein, we focus on the evolution of chemical defenses in the butterfly tribe Heliconiini. These neotropical butterflies contain large concentrations of cyanogenic glucosides, cyanide-releasing compounds acting as predator deterrent. These compounds are either de novo synthesized or sequestered from their Passiflora host plant, so that their concentrations may depend on host plant specialization and host plant availability. We sampled 375 wild Heliconiini butterflies across Central and South America, covering 43% species of this clade, and quantify individual variations in the different CGs using liquid chromatography coupled with tandem mass spectrometry. We detected new compounds and important variations in chemical defenses both within and among species. Based on the most recent and well-studied phylogeny of Heliconiini, we show that ecological factors such as mimetic interactions and host plant specialization have a significant association with chemical profiles, but these effects are largely explained by phylogenetic relationships. Our results therefore suggest that shared ancestries largely contribute to chemical defense variation, pointing out at the interaction between historical and ecological factors in the evolution of Mullerian mimicry.

KW - aposematism

KW - cyanogenic glucosides

KW - Heliconius

KW - LC-MS

KW - MS

KW - Mullerian mimicry

KW - phylogenetic signal

KW - JACAMARS GALBULA-RUFICAUDA

KW - R-PACKAGE

KW - CYANOGENIC GLYCOSIDES

KW - PHYLOGENETIC SIGNAL

KW - MIMICRY

KW - RESPONSES

KW - BIOLOGY

KW - PREY

KW - DIVERSIFICATION

KW - SEQUESTRATION

U2 - 10.1002/ece3.6044

DO - 10.1002/ece3.6044

M3 - Review

C2 - 32185010

VL - 10

SP - 2677

EP - 2694

JO - Ecology and Evolution

JF - Ecology and Evolution

SN - 2045-7758

IS - 5

ER -