Batesian mimicry has evolved with deleterious effects of the pleiotropic gene doublesex

Shinya Komata,Haruhiko Fujiwara,Tasuku Kitamura

doi:10.1038/s41598-020-78055-1

Abstract

Dimorphic female-limited Batesian mimicry in the swallowtail butterfly Papilio polytes is regulated by the supergene locus H, harbouring the mimetic (H) and non-mimetic (h) doublesex (dsx) gene. In the present study, we demonstrated that dsx-H negatively affects the number of eggs laid, hatching rate, larval survival rate, and adult lifespan. When crossed with hh males, the number of eggs laid of mimetic females (genotype HH) was lower than that of non-mimetic females (hh). Moreover, hh and Hh females laid fewer eggs when crossed with HH males. The hatching and larval survival rates were lower when both female and male parents harboured dsx-H. The adult lifespan of HH females was shorter than that of hh females, while it was similar in males regardless of the genotype. These findings suggest the presence of a cost–benefit balance of Batesian mimicry, which is evolved to avoid predation but is accompanied by physiological deficits, in this species.

Highlights

Dimorphic female-limited Batesian mimicry in the swallowtail butterfly Papilio polytes is regulated by the supergene locus H, harbouring the mimetic (H) and non-mimetic (h) doublesex gene
Survival rate in juvenile period decreased over generations (F0–F2) in lines derived from mothers with mimetic phenotypes, suggesting a mild deleterious effect of dsx-H20
To examine whether the evolution of Batesian mimicry in Papilio polytes is accompanied by physiological deficits, we explored the effects of dsx-H on various traits other than mimetic ones using three experiments each (1) exploring the frequency of dsx genotypes in the wild, (2) examining the effects of parental genotypes on fecundity and larval performance, and (3) examining the effects of genotypes on larval development and adult lifespan

Summary

Introduction

Dimorphic female-limited Batesian mimicry in the swallowtail butterfly Papilio polytes is regulated by the supergene locus H, harbouring the mimetic (H) and non-mimetic (h) doublesex (dsx) gene. We compared the number of eggs laid, hatching rate, and larval survival rate using crosses between females and males with all combinations of dsx genotypes (hh♂ × hh♀, Hh♂ × hh♀, HH♂ × hh♀, hh♂ × Hh♀, Hh♂ × Hh♀, HH♂ × Hh♀, hh♂ × HH♀, Hh♂ × HH♀, and HH♂ × HH♀).

Results

Conclusion