Sexual signaling by females: do unmated females increase their signaling effort?

Theory predicts that females should invest least in mate searching when young, but increase their effort with age if they remain unmated. Few studies have examined variation in female sexual signalling. Female Dawson's burrowing bees (Amegilla dawsoni) search for males by signalling their receptivity on emergence, but many leave the emergence site unmated and must attract males at feeding sites. Female bees prevented from mating on emergence had more extreme versions of cuticular hydrocarbon profiles that make them attractive to males, lending empirical evidence of adaptive shifts in female mating effort.

理论预测，雌性个体在年轻阶段应最小化配偶搜寻的资源投入，但若始终未完成交配，则会随年龄增长提升搜寻努力程度。目前鲜有研究探讨雌性性信号的表达变异。道森隧蜂（Amegilla dawsoni）的雌性个体在羽化阶段通过传递其交配接受信号来搜寻雄性，但多数个体在羽化后并未成功交配，因此需要在觅食场所吸引雄性。被阻断羽化后即时交配的雌性隧蜂，其表皮碳氢化合物（cuticular hydrocarbon）谱型会呈现更为极端的特征，这类特征可增强其对雄性的吸引力，该发现为雌性交配投入的适应性转变提供了实证支撑。