North Carolina State University, Department of Entomology and Plant Pathology and W.M. Keck Center for Behavioral Biology, Raleigh, North Carolina, USA.
Sci Rep. 2019 Feb 27;9(1):2942. doi: 10.1038/s41598-019-39868-x.
The antennae of adult male German cockroaches detect a contact sex pheromone embedded in the female's cuticular lipids. The female pheromone stimulates courtship behavior in males, notably a wing-raising (WR) display. Within aggregations, however, cuticular lipids are disseminated by contact among group members, including nymphs and adults of both sexes, and "contamination" of cockroaches with the cuticular lipids of another stage or sex may interfere with sex discrimination and disrupt courtship. We used behavioral observations, bioassays and chemical analysis to determine how males maintain their sensitivity to sex pheromone in aggregations. Males contaminated with female pheromone displayed lower courtship, because residual female pheromone on their antennae adapted their peripheral sensilla and habituated the central nervous system. Female pheromone that contaminated the male's antennae also elicited courtship from other non-contaminated males, disrupting their sex discrimination in the group. However, antennal grooming effectively removed female pheromone from males' antennae and maintained their chemosensory acuity and sexual discrimination among group members. Thus, grooming of the antennae and other sensory appendages is an important strategy to enhance sensory acuity, especially in group-living insects like the German cockroach.
成年德国蟑螂雄虫的触角可以探测到雌性蟑螂表皮脂质中嵌入的接触性性信息素。这种雌性信息素可以刺激雄性的求偶行为，特别是翅膀抬高（WR）展示。然而，在群体中，表皮脂质通过群体成员之间的接触而传播，包括若虫和雌雄两性成虫，并且另一阶段或性别的蟑螂的“污染”可能会干扰性别的识别并破坏求偶行为。我们使用行为观察、生物测定和化学分析来确定雄性在群体中如何保持对性信息素的敏感性。被雌性信息素污染的雄性表现出较低的求偶行为，因为它们触角上残留的雌性信息素适应了其外周感觉器官，并使中枢神经系统习惯化。污染雄性触角的雌性信息素也会引起其他未被污染的雄性的求偶行为，从而破坏它们在群体中的性别识别。然而，触角的梳理可以有效地从雄性触角上去除雌性信息素，从而保持它们在群体成员中的化学感觉敏锐度和性别的识别能力。因此，触角和其他感觉附属物的梳理是增强感觉敏锐度的重要策略，尤其是对于像德国蟑螂这样的群居昆虫。
