Evolution of sexual conflict in scorpionflies
Abstract
Sexual conflict - opposite reproductive/genetic interests between sexes - can be a significant driver of insect evolution. Scorpionflies (Insecta: Mecoptera) are models in sexual conflict research due to their large variety of mating practices, including coercive behaviour and nuptial gift provisioning. However, the role of palaeontology in sexual conflict studies remains negligible, namely due to the paucity of well-preserved fossils. Here we describe three male scorpionflies from Cretaceous and Eocene ambers. The structure of notal and postnotal organs is analysed in extant and extinct forms; a depression below the base of the notal organ in different panorpid species spatially matches the anterior fold of the female's wing. Based on disparate abdominal configurations and correlations in extant relatives, we posit that each new fossil taxon had a different mating approach along a nuptial gifting-coercive spectrum. The Eocene specimen possesses extreme female clamping abdominal armature, suggesting a degree of sexual coercion greater than in any other known scorpionfly, extinct or extant. The fossil record of abdominal modifications in male scorpionflies documents a relatively late evolution (Eocene) of long notal organs indicating oppressive behaviour toward a female during mating. Our findings reveal a wider array of mating-related morphological specialisations among extinct Panorpoidea, likely reflecting more diversified past mating strategies and behaviours in this group, and represent first steps towards gaining a deep-time perspective on the evolution of sexual conflict over mating among insects.
Data availability
All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Additional information related to this paper may be requested from the authors. Investigated fossils are available in public institutions: at the Institutional Collection from the El Soplao Cave (Government of Cantabria), Celis, Cantabria, N Spain and at the collection from the Museum of the Institute of Systematics and Evolution of Animals (ISEA), Polish Academy of Sciences (PAS), Kraków, Poland.
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Author details
Funding
National Science Center, Poland (2013/09/B/NZ8/03270)
- Agnieszka Soszyńska-Maj
- Katarzyna Kopeć
- Wieslaw Krzemiński
National Science Center, Poland (2016/23/B/NZ8/00936)
- Agnieszka Soszyńska-Maj
- Ewa Krzemińska
- Kornelia Skibińska
- Katarzyna Kopeć
- Wieslaw Krzemiński
AEI/FEDER, UE (CGL2017-84419)
- Ricardo Pérez-de la Fuente
High-level Talents, Dali University (KY2096124040)
- Ji-Shen Wang
National Science Center, Poland (2018/31/B/NZ8/02113)
- Krzysztof Szpila
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- David Lentink, University of Groningen, Netherlands
Version history
- Received: May 18, 2021
- Accepted: February 10, 2022
- Accepted Manuscript published: February 11, 2022 (version 1)
- Version of Record published: April 5, 2022 (version 2)
Copyright
© 2022, Soszyńska-Maj et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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