Male sexually coercive behaviour drives increased swimming efficiency in female guppies

Sexual coercion of females by males is widespread across sexually reproducing species. It stems from a conflict of interest over reproduction and exerts selective pressure on both sexes. For females, there is often a significant energetic cost of exposure to male sexually coercive behaviours. Our understanding of the efficiency of female resistance to male sexually coercive behaviour is key to understanding how sexual conflict contributes to population level dynamics and ultimately to the evolution of sexually antagonistic traits. Overlooked within this context are plastic physiological responses of traits within the lifetime of females that could moderate the energetic cost imposed by coercive males. Here, we examined whether conflict over the frequency and timing of mating between male and female guppies Poecilia reticulata can induce changes in swimming performance and aerobic capacity in females as they work to escape harassment by males. Females exposed to higher levels of harassment over a 5-month period used less oxygen to swim at a given speed, but displayed no difference in resting metabolic rate, maximal metabolic rate, maximal sustained swimming speed or aerobic scope compared to females receiving lower levels of harassment. The observed increase in swimming efficiency is at least partially related to differences in swimming mechanics, likely brought on by a training effect of increased activity, as highly harassed females spent less time performing pectoral fin-assisted swimming. Sexual conflict results in sexually antagonistic traits that impose a variety of costs, but our results show that females can reduce costs through phenotypic plasticity. It is also possible that phenotypic plasticity in swimming physiology or mechanics in response to sexual coercion can potentially give females more control over matings and affect which male traits are under selection.

Keyword(s)

locomotion, metabolic rate, phenotypic plasticity, sexual conflict, teleost fish

Full Text

FilePagesSizeAccess
Publisher's official version
8176 Ko
Lay Summary
181 Ko
Fig. S1. Comparison the remaining aerobic scope, after accounting for the costs of locomotion, while swimming at various speeds for females guppies ...
-2 Mo
Fig. S2. Relationship between critical swimming speed (Ucrit) and mean pectoral fin use during aerobically powered swimming in female...
-2 Mo
Table S1. Morphological comparisons between female guppies reared for several months with exposure to varying ...
181 Ko
How to cite
Killen Shaun S., Croft Darren P., Salin Karine, Darden Safi K. (2016). Male sexually coercive behaviour drives increased swimming efficiency in female guppies. Functional Ecology. 30 (4). 576-583. https://doi.org/10.1111/1365-2435.12527, https://archimer.ifremer.fr/doc/00414/52502/

Copy this text