Data from: Replicated evolutionary divergence in the cuticular hydrocarbon profile of male crickets associated with the loss of song in the Hawaiian archipelago

Simmons et. al. -J-Evol-Biol-2014: Raw peak areas of cuticular hydrocarbon compounds found on male crickets using GCMS

Female choice based on male secondary sexual traits is well documented, although the extent to which this selection can drive an evolutionary divergence in male traits among populations is less clear. Male field crickets Teleogryllus oceanicus attract females using a calling song and once contacted switch to courtship song to persuade them to mate. These crickets also secrete onto their cuticle a cocktail of long-chained fatty acids or cuticular hydrocarbons (CHCs). Females choose among potential mates based on the structure of male acoustic signals and on the composition of male CHC profiles. Here, we utilize two naturally occurring mutations that have arisen independently on two Hawaiian islands and render the male silent to ask whether the evolutionary loss of acoustic signalling can drive an evolutionary divergence in the alternative signalling modality, male CHC profiles. QST-FST comparisons revealed strong patterns of CHC divergence among three populations of crickets on the islands of Hawaii, Oahu and Kauai. Contrasts between wild-type and flatwing males on the islands of Oahu and Kauai indicated that variation in male CHC profiles within populations is associated with the loss of acoustic signalling; flatwing males had a relatively low abundance of long-chained CHCs relative to the short-chained CHCs that females find attractive. Given their dual functions in desiccation resistance and sexual signalling, insect CHCs may be particularly important traits for reproductive isolation and ultimately speciation.

Simmons等人，《J-Evol-Biol》，2014年：利用气相色谱-质谱联用（GCMS）技术检测得到的雄性田野蟋蟀（Teleogryllus oceanicus）体表表皮碳氢化合物（cuticular hydrocarbon, CHC）的原始峰面积。基于雄性第二性征的雌性择偶行为已有充分研究证实，但此类选择在多大程度上可推动不同种群间雄性性状的演化分化，目前仍不甚明确。该种蟋蟀通过鸣唱声吸引雌性，在雌性接触后则切换为求偶鸣唱以促成交配。其体表还会分泌长链脂肪酸混合物或表皮碳氢化合物（CHCs）。雌性会依据雄性的声学信号结构以及雄性表皮碳氢化合物谱（CHC profiles）的组成来筛选潜在配偶。本研究借助两个独立起源于夏威夷两座不同岛屿的自然突变体——该突变使雄性丧失鸣唱能力——来探究：声学信号的演化丢失是否会推动另一信号通路——雄性表皮碳氢化合物谱——产生演化分化。QST-FST比较分析显示，夏威夷岛、瓦胡岛与考爱岛的三个蟋蟀种群间存在显著的表皮碳氢化合物分化模式。对瓦胡岛和考爱岛上的野生型与平翅型雄性的对比研究表明，种群内雄性表皮碳氢化合物谱的变异与声学信号的丢失存在关联：相较于雌性偏好的短链表皮碳氢化合物，平翅型雄性的长链表皮碳氢化合物相对丰度更低。鉴于昆虫表皮碳氢化合物兼具抗脱水胁迫与性信号传递的双重功能，其可能是推动生殖隔离乃至最终物种形成的关键性状。