Data from: Gustatory polymorphism mediates a new adaptive courtship strategy

Human-imposed selection can lead to adaptive changes in sensory traits. However, rapid evolution of the sensory system can interfere with other behaviors, and animals must overcome such sensory conflicts. In response to insecticide baits that contain glucose, German cockroaches evolved glucose-aversion (GA), which confers behavioral resistance against baits. During courtship, the male offers the female a nuptial gift that contains maltose, which expediates copulation. However, the female's saliva rapidly hydrolyzes maltose into glucose, which causes GA females to dismount the courting male, which reduces mating success of GA females. Comparative analysis revealed two adaptive traits in GA males. They produce maltotriose, which is more resilient to salivary glucosidases, and they initiate copulation faster than wild-type (WT) males, before GA females interrupt their nuptial feeding and dismount the male. Recombinant lines of the two strains showed that the two emergent traits of GA males were not genetically associated with the GA trait. Results suggest that the two courtship traits emerged in response to the altered sexual behavior of GA females and independently of the male's GA trait. Although rapid adaptive evolution generates sexual mismatches that lower fitness, compensatory behavioral evolution can correct these sensory discrepancies.