School of BioSciences, University of Melbourne, Melbourne, Victoria 3010, Australia.
Biol Lett. 2020 Dec;16(12):20200614. doi: 10.1098/rsbl.2020.0614. Epub 2020 Dec 2.
Juvenile population density has profound effects on subsequent adult development, morphology and reproductive investment. Yet, little is known about how the juvenile social environment affects adult investment into chemical sexual signalling. Male gumleaf skeletonizer moths, facultatively increase investment into antennae (pheromone receiving structures) when reared at low juvenile population densities, but whether there is comparable adjustment by females into pheromone investment is not known. We investigate how juvenile population density influences the 'calling' (pheromone-releasing) behaviour of females and the attractiveness of their pheromones. Female adjust their calling behaviour in response to socio-sexual cues: adult females reared in high juvenile population densities called earlier and for longer than those from low juvenile densities. Juvenile density also affected female pheromonal attractiveness: Y-maze olfactometer assays revealed that males prefer pheromones produced by females reared at high juvenile densities. This strategic investment in calling behaviour by females, based on juvenile cues that anticipate the future socio-sexual environment, likely reflects a response to avoid mating failure through competition with neighbouring signallers.
幼年种群密度对后续的成年发育、形态和生殖投资有深远影响。然而，对于幼年社会环境如何影响成年对化学性信息素信号的投资，人们知之甚少。雄性胶叶 skeletonizer 蛾在幼年种群密度低时，会选择性地增加触角（信息素接收结构）的投资，但雌性是否有类似的信息素投资调整尚不清楚。我们研究了幼年种群密度如何影响雌性的“鸣叫”（释放信息素）行为以及它们信息素的吸引力。雌性会根据社会性线索来调整鸣叫行为：在高幼年种群密度下饲养的成年雌性比在低幼年种群密度下饲养的雌性更早和更长时间地鸣叫。幼年密度也影响了雌性的信息素吸引力：Y 型嗅觉仪测定表明，雄性更喜欢在高幼年密度下饲养的雌性产生的信息素。这种基于幼年线索的雌性鸣叫行为的策略性投资，预计是为了避免因与邻近信号传递者竞争而导致交配失败的一种反应。
