Sexual selection gradients change over time in a simultaneous hermaphrodite
Abstract
Sexual selection is generally predicted to act more strongly on males than on females. The Darwin-Bateman paradigm predicts that this should also hold for hermaphrodites. However, measuring this strength of selection is less straightforward when both sexual functions are performed throughout the organism's lifetime. Besides, quantifications of sexual selection are usually done during a short time window, while many animals store sperm and are long-lived. To explore whether the chosen timeframe affects estimated measures of sexual selection, we recorded mating success and reproductive success over time, using a simultaneous hermaphrodite. Our results show that male sexual selection gradients are consistently positive. However, an individual's female mating success seems to negatively affect its own male reproductive success, an effect that only becomes visible several weeks into the experiment, highlighting that the timeframe is crucial for the quantification and interpretation of sexual selection measures, an insight that applies to any iteroparous mating system.
Article and author information
Author details
Funding
Nederlandse Organisatie voor Wetenschappelijk Onderzoek (816.01.009)
- Joris M Koene
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, Stanford University, United States
Version history
- Received: January 14, 2017
- Accepted: June 13, 2017
- Accepted Manuscript published: June 14, 2017 (version 1)
- Version of Record published: July 14, 2017 (version 2)
Copyright
© 2017, Hoffer 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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