Justus Kevin T, Mendelson Tamra C
Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, MD 21250, USA.
Behav Processes. 2018 Jun;151:6-10. doi: 10.1016/j.beproc.2018.02.024. Epub 2018 Mar 1.
The higher energetic cost related to female gamete investment is classically considered the driving force behind sexual selection. This asymmetric cost of reproduction is thought to cause female preference for elaborate male ornamentation. Subsequent co-evolution of female preferences and male ornaments is thought then to lead to a greater preference for conspecific mates in females as compared to males. Thus, female choice is classically assumed to contribute more than male choice to behavioral isolation between sexually dimorphic species. However, this hypothesis fails to account for the cost of maintaining a territory, building a nest, courtship displays, ornament investment, and parental care, as seen in males of the Siamese fighting fish, Betta splendens. Here we show that male B. splendens have a greater preference for female conspecifics than females have for male conspecifics, when given a choice between conspecifics and the allopatric Betta imbellis. We hypothesize that in B. splendens, the cost of mating may be higher for males than females, and predict that male choice would contribute to behavioral isolation upon secondary contact of wild populations.
与雌配子投资相关的更高能量成本传统上被认为是性选择背后的驱动力。这种不对称的繁殖成本被认为会导致雌性对精致雄性装饰的偏好。随后，雌性偏好和雄性装饰的共同进化被认为会导致雌性比雄性更倾向于选择同种配偶。因此，传统观点认为，在两性异形物种之间的行为隔离中，雌性选择比雄性选择的作用更大。然而，这一假设无法解释维持领地、筑巢、求偶展示、装饰投资和亲代抚育的成本，暹罗斗鱼（Betta splendens）的雄性就是如此。在这里，我们表明，当在同种和异域的美丽斗鱼（Betta imbellis）之间进行选择时，暹罗斗鱼雄性对同种雌性的偏好大于雌性对同种雄性的偏好。我们假设，在暹罗斗鱼中，雄性的交配成本可能高于雌性，并预测雄性选择将在野生种群二次接触时导致行为隔离。
