Department of Biology, University of Toronto at Mississauga, Mississauga, Ontario, Canada L5L 1C6.
J Evol Biol. 2010 Jul;23(7):1528-37. doi: 10.1111/j.1420-9101.2010.02021.x. Epub 2010 May 26.
Although many studies examine the form of sexual selection in males, studies characterizing this selection in females remain sparse. Sexual selection on females is predicted for sex-role-reversed Mormon crickets, Anabrus simplex, where males are choosy of mates and nutrient-deprived females compete for matings and nutritious nuptial gifts. We used selection analyses to describe the strength and form of sexual selection on female morphology. There was no positive linear sexual selection on the female body size traits predicted to be associated with male preferences and female competition. Instead, we detected selection for decreasing head width and mandible length, with stabilizing selection as the dominant form of nonlinear selection. Additionally, we tested the validity of a commonly used instantaneous measure of mating success by comparing selection results with those determined using cumulative mating rate. The two fitness measures yielded similar patterns of selection, supporting the common sampling method comparing mated and unmated fractions.
虽然许多研究都考察了雄性的性选择形式,但描述雌性性选择的研究仍然很少。在性角色颠倒的摩门蟋蟀 Anabrus simplex 中,雄性对配偶很挑剔,而营养匮乏的雌性则会为交配和营养丰富的婚礼礼物而竞争,因此预测雌性会受到性选择的影响。我们使用选择分析来描述雌性形态的性选择的强度和形式。没有正线性选择对与雄性偏好和雌性竞争相关的雌性体型特征进行选择。相反,我们检测到对头宽和下颚长度的选择呈下降趋势,而稳定选择是非线性选择的主要形式。此外,我们通过比较使用交配率累积值确定的选择结果与使用常用的瞬时交配成功率测量值来检验其有效性。这两种适应度衡量标准产生了相似的选择模式,支持了比较交配和未交配分数的常用抽样方法。