Publication Date:
2007-05-01
Description:
The mating system of eastern mosquito fish (Gambusia holbrooki) is dominated by male sexual coercion, where all matings are forced and females never appear to cooperate and actively avoid all attempts. Previous research has shown that maleG. holbrookioffer a model system for examining the benefits of reversible thermal acclimation for reproductive success, but examining the benefits to female avoidance behaviour has been difficult. In this study, we examined the ability of non-male-deprived femaleG. holbrookito avoid forced–coercive matings following acclimation to either 18 or 30°C for six weeks (12 h light : 12 h dark photoperiod). Thermal acclimation of burst and sustained swimming performance was also assessed, as these traits are likely to underlie their ability to avoid forced matings. There was no influence of thermal acclimation on the burst swimming performance of femaleG. holbrookiover the range 18–30°C; however, sustained swimming performance was significantly lower in the warm- than the cool-acclimation group. For mating behaviour, we tested the hypothesis that acclimation would enhance the ability of femaleG. holbrookito avoid forced matings at their host acclimation temperature relative to females acclimated to another environment. However, our hypothesis was not supported. The rate of copulations was almost three times greater for females acclimated to 30°C than 18°C when tested at 30°C, indicating that they possess the ability to alter their avoidance behaviour to ‘allow’ more copulations in some environments. Coupled with previous studies, femaleG. holbrookiappear to have greater control on the outcome of coercive mating attempts than previously considered and can alter their propensity to receive forced matings following thermal acclimation. The significance of this change in female mating-avoidance behaviours with thermal acclimation remains to be explored.
Print ISSN:
0962-8436
Electronic ISSN:
1471-2970
Topics:
Biology
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