Macroevolutionary origin and adaptive function of a polymorphic female signal involved in sexual conflict

Research output: Contribution to journalArticle

Abstract

Intersexual signals that reveal developmental or mating status in females have evolved repeatedly in many animal lineages. Such signals have functions in sexual conflict over mating and can therefore influence sexually antagonistic coevolution. However, we know little about how female signal development modifies male mating harassment and thereby sexual conflict. Here, we combine phylogenetic comparative analyses of a color polymorphic damselfly genus (Ischnura) with behavioral experiments in one target species to investigate the evolutionary origin and current adaptive function of a developmental female color signal. Many Ischnura species have multiple female color morphs, which include a male-colored morph (male mimics) and one or two female morphs that differ markedly from males (heterochrome females). In Ischnura elegans, males and male-mimicking females express a blue abdominal patch throughout postemergence life. Using phenotypic manipulations, we show that the developmental expression of this signaling trait in heterochrome females reduces premating harassment prior to sexual maturity. Across species this signal evolved repeatedly, but in heterochrome females its origin is contingent on the signal expressed by co-occurring male-mimicking females. Our results suggest that the co-option of a male-like trait to a novel female anti-harassment function plays a key role in sexual conflict driven by premating interactions.

Details

Authors
Organisations
External organisations
  • Great Basin College
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Evolutionary Biology

Keywords

  • Cross-sexual transfer, Male mating harassment, Male mimicry, Sex-limited polymorphism, Sexual dimorphism, Sexually antagonistic coevolution
Original languageEnglish
JournalAmerican Naturalist
Publication statusE-pub ahead of print - 2019
Publication categoryResearch
Peer-reviewedYes