Data from: Sex-specific genotype-by-environment interactions for cuticular hydrocarbon expression in decorated crickets, Gryllodes sigillatus: implications for the evolution of signal reliability

Phenotypic traits that convey information about individual identity or quality are important in animal social interactions, and the degree to which such traits are influenced by environmental variation can have profound effects on the reliability of these cues. Using inbred genetic lines of the decorated cricket, Gryllodes sigillatus, we manipulated diet quality to test how the cuticular hydrocarbon (CHC) profiles of males and females respond across two different nutritional rearing environments. There were significant differences between lines in the CHC profiles of females, but the effect of diet was not quite statistically significant. There was no significant genotype-by-environment interaction (GEI), suggesting that environmental effects on phenotypic variation in female CHCs are independent of genotype. There was, however, a significant effect of GEI for males, with changes in both signal quantity and content, suggesting that environmental effects on phenotypic expression of male CHCs are dependent on genotype. The differential response of male and female CHC expression to variation in the nutritional environment suggests that these chemical cues may be under sex-specific selection for signal reliability. Female CHCs show the characteristics of reliable cues of identity: high genetic variability, low condition dependence, and a high degree of genetic determination. This supports earlier work showing that female CHCs are used in self-recognition to identify previous mates and facilitate polyandry. In contrast, male CHCs show the characteristics of reliable cues of quality: condition dependence and a relatively higher degree of environmental determination. This suggests that male CHCs are likely to function as cues of underlying quality during mate choice and/or male dominance interactions.

能够传递个体身份或品质信息的表型性状，在动物社会互动中发挥着关键作用；此类性状受环境变异影响的程度，会对这些信号的可靠性产生深远影响。本研究以装饰蟋蟀（Gryllodes sigillatus）的近交遗传品系为实验材料，通过调控日粮品质，探究雌雄个体的表皮碳氢化合物（cuticular hydrocarbon, CHC）谱在两种不同营养饲养环境下的响应模式。雌性个体的CHC谱在不同品系间存在显著差异，但日粮的影响未达到统计学显著性水平。基因型-环境互作（genotype-by-environment interaction, GEI）未在雌性个体中表现出显著效应，提示环境对雌性CHC表型变异的影响与基因型相互独立。然而雄性个体的CHC谱则存在显著的GEI效应，其信号的数量与组成均发生改变，表明环境对雄性CHC表型表达的影响依赖于基因型。雌雄CHC表达对营养环境变异的响应存在显著差异，这提示这类化学信号可能受到了针对信号可靠性的性别特异性选择压力。雌性CHC具备作为身份可靠信号的典型特征：较高的遗传变异度、较低的状态依赖性，以及高度的遗传决定特性。这与此前的研究结论一致，即雌性CHC可用于自我识别，以辨识过往交配过的配偶并促进多雄交配行为。与之相反，雄性CHC则具备作为品质可靠信号的特征：状态依赖性以及相对更高的环境决定程度。这表明雄性CHC可能在配偶选择以及雄性支配互动中，作为反映个体内在品质的信号发挥功能。