Data from: Tolerance requires the right smell: first evidence for interspecific selection on chemical recognition cues

The integument of insects is generally covered with cuticular hydrocarbons (CHC). They serve multiple functions, most prominent among them waterproofing and – especially among social insects – as communication signal. CHC profiles are incredibly diverse within and across species. However, the causes for CHC variation between species, and potential selection pressures that may shape CHC profiles, are hardly understood. Here, we investigated potential selection pressures on ant CHC. We tested the hypotheses that living in association with another species (e.g., parabiosis), and the climate of the ant’s habitat, affect CHC composition. We conducted a large-scale comparison of 37 Camponotus species from five continents. Our results demonstrate that closely associated ant species possess significantly longer hydrocarbons and higher proportions of methylbranched alkenes and alkadienes than non- or loosely associated species. In contrast, climatic factors had no effects. This study shows that the need to be tolerated by another species greatly affects CHC profiles.

昆虫体壁通常覆盖有表皮碳氢化合物（cuticular hydrocarbons, CHC）。这类物质具备多种生理功能，其中最核心的为防水作用，而在社会性昆虫中，其还可充当通讯信号。不同物种之间以及同一物种内部，CHC谱型均呈现出极高的多样性。然而，学界对物种间CHC差异的成因，以及可能塑造CHC谱型的潜在选择压力，尚未得到清晰阐释。本研究围绕蚂蚁CHC的潜在选择压力展开探究，验证了以下假说：与其他物种形成共生关系（例如联合共生（parabiosis））以及蚂蚁栖息地的气候，会对CHC组成产生影响。我们对来自五大洲的37种弓背蚁（Camponotus）开展了大规模比较分析。研究结果显示，与其他物种紧密共生的蚂蚁类群，其体表碳氢化合物链长显著更长，且甲基支链烯烃、双烯烃的占比显著高于非共生或松散共生的类群。与之相反，气候因素未产生显著影响。本研究证实，需被其他物种容忍的生存需求，会对CHC谱型产生极为显著的调控作用。