Document Type
Article
Publication Title
Evolution
Publication Date
3-2024
Keywords
behavioral plasticity, calling effort, crickets, experimental evolution, operational sex ration, sexual selection
Abstract
The operational sex ratio (OSR) is a key component influencing the magnitude of sexual selection driving the evolution of male sexual traits, but males often also retain the ability to plastically modulate trait expression depending on the current environment. Here we employed an experimental evolution approach to determine whether the OSR affects the evolution of male calling effort in decorated crickets, a costly sexual trait, and whether plasticity in calling effort is altered by the OSR under which males have evolved. Calling effort of males from 2 selection regimes maintained at different OSRs over 18–20 generations (male vs. female biased) was recorded at 2 different levels of perceived competition, in the absence of rivals or in the presence of an experimentally muted competitor. The effect of the OSR on the evolution of male calling effort was modest, and in the opposite direction predicted by theory. Instead, the immediate competitive environment strongly influenced male calling effort as males called more in the presence of a rival, revealing considerable plasticity in this trait. This increased calling effort came at a cost, however, as males confined with a muted rival experienced significantly higher mortality.
Funding Source
This research was funded by Weigel grants from the Beta Lambda Chapter of the Phi Sigma Biological Honor Society, the Theodore J. Cohn grant from the Orthopterists’ Society, and the E. L. Mockford and C. F. Thompson Summer Research Fellowship to J.T.M., a grant from the Undergraduate Research Support Program at Illinois State University to W.K., a grant from the Australian Research Council (DP180101708) to J.H., and a grant from the National Science Foundation (IOS 16–54028) to S.K.S., B.M.S., and J.H.
Recommended Citation
McKermitt, J.T., Foquet, B., Kuna, W., Hunt, J., Sadd, B.M. and Sakaluk, S.K. 2024. Experimental evolution under varying sex ratio and behavioral plasticity in response to perceived competitive environment independently affect calling effort in male crickets. Evolution 78: 453-462. https://doi.org/10.1093/evolut/qpad224
DOI
10.1093/evolut/qpad224
Comments
This is the accepted manuscript of an article first published in Evolution (2024): https://doi.org/10.1093/evolut/qpad224