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bioRxiv · 10.1101/430322

Escalation and constraints of antagonistic armaments in water striders

Crumiere, A. J. J.·Armisen, D.·Vargas-Lowman, A.·Kubarakos, M.·Moreira, F. F. F.·Khila, A.
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Abstract

Sexual conflict may result in the escalating coevolution of sexually antagonistic traits. However, our understanding of the evolutionary dynamics of antagonistic traits and their role in association with sex-specific escalation remains limited. Here we study sexually antagonistic coevolution in a genus of water striders called Rhagovelia. We identified a set of male grasping traits and female anti-grasping traits used during pre-mating struggles and show that natural variation of these traits is associated with variation in mating performance in the direction expected for antagonistic co-evolution. Phylogenetic mapping detected signals of escalation of these sexually antagonistic traits suggesting an ongoing arms race. Moreover, their escalation appears to be constrained by a trade-off with dispersal through flight in both sexes. Altogether our results highlight how sexual interactions may have shaped sex-specific antagonistic traits and how constraints imposed by natural selection may have influenced their evolution.

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Crumiere, A. J. J., Armisen, D., Vargas-Lowman, A., Kubarakos, M., Moreira, F. F. F., Khila, A.. 2018-09-29. Escalation and constraints of antagonistic armaments in water striders. https://doi.org/10.1101/430322

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