Male moths that shed their genital spines inside the female: A survey of male mating costs and material investment during copulation
- Published
- Accepted
- Subject Areas
- Ecology, Entomology, Evolutionary Studies, Zoology
- Keywords
- Male mating costs, Sexual selection, Ejaculate, Longevity, Genital spines, Lepidoptera, Tortricidae, Amorbia
- Copyright
- © 2016 Camacho-García et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- (2016) Male moths that shed their genital spines inside the female: A survey of male mating costs and material investment during copulation. PeerJ Preprints 4:e2598v1 https://doi.org/10.7287/peerj.preprints.2598v1
Abstract
In some insects, males produce costly ejaculates that reduce the typical sexual imbalance in potential reproductive rates thus influencing the mode and intensity of sexual selection. In Lepidoptera, in particular, males tend to invest heavily in mate searching, courtship and ejaculate production; furthermore, in some species males shed genital spines (deciduous cornuti) within the female genital tract during copulation. We studied experimentally the potential mating costs incurred by males of a moth with deciduous cornuti, Amorbia cuneana (Tortricidae). In the first experiment, we tested the prediction that mating costs result in a reduction in male longevity and survival rate. Our results did not support this prediction because virgin and mated males had similar longevity and survival rate. This result is somewhat surprising considering the substantial resource investment in mating found in the second experiment. In their first mating males invested in the ejaculate 9% of their body weight and transferred virtually all their deciduous cornuti; furthermore, few males were able to mate a second time (although we do not know if this was due to female rejection), these males produced smaller ejaculates and there was no evidence of cornuti regrowth. We hypothesize that reduced mating opportunities have selected for males that are ready to transfer large ejaculates at any moment and thus against the diversion of resources from reproductive tissues to somatic maintenance in unmated males; the transfer of the full set of deciduous cornuti in first copulations is consistent with this hypothesis.
Author Comment
This is a submission to PeerJ for review.
Supplemental Information
Dataset
A. Dataset of the "Survival Costs" Experiment
B. Dataset of the "Relative Investment" Experiment
C. Weight of the corpus bursae of virgin females