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Reproductive traits that influence female remating and competitive fertilization rapidly evolve in response to sexual selection and sexual conflict. One such trait, observed across diverse animal taxa, is the formation of a structural plug inside the female reproductive tract (FRT), either during or shortly after mating. In Drosophila melanogaster , male seminal fluid forms a mating plug inside the female bursa, which has been demonstrated to influence sperm entry into storage and latency of female remating. Processing of the plug, including its eventual ejection from the female's reproductive tract, influences the competitive fertilization success of her mates and is mediated by female × male genotypic interactions. However, female contributions to plug formation and processing have received limited attention. Using developmental mutants that lack glandular FRT tissues, we reveal that these tissues are essential for mating plug ejection. We further use proteomics to demonstrate that female glandular proteins, and especially proteolytic enzymes, contribute to mating plug composition and have a widespread impact on plug formation and composition. Together, these phenotypic and molecular data identify female contributions to intersexual interactions that are a potential mechanism of post-copulatory sexual selection.
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Male Superb Lyrebirds ( Menura novaehollandiae ) perform an ornate multimodal display immediately following copulation
Birds perform some of the most elaborate intersexual displays in the animal kingdom, but while these are typically associated with the pre‐copulation stage of sexual interactions, the males of some species also display following copulation. Here we report that immediately after dismounting from females, male Superb LyrebirdsMenura novaehollandiaeperform a striking multimodal display comprising a repetitive clicking vocalization and a stereotyped tail posture, while walking backwards away from the female. This ubiquitous postcopulatory display constitutes the fourth, structurally distinct multimodal display performed by male Superb Lyrebirds during intersexual interactions and points to a role for sexual selection after copulation in the lyrebird's lek‐like mating system. As such, this study highlights an additional and largely overlooked functional context for complex courtship choreography in birds.
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- Award ID(s):
- 1755132
- PAR ID:
- 10446112
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Ibis
- Volume:
- 164
- Issue:
- 3
- ISSN:
- 0019-1019
- Page Range / eLocation ID:
- p. 809-815
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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