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.

昆虫的体表通常覆盖有表皮碳氢化合物（cuticular hydrocarbons, CHC）。这类物质具备多重生理功能，其中最突出的两项分别是防水性，以及在社会性昆虫中尤为关键的通讯信号传递功能。不同物种间乃至同一物种内部的表皮碳氢化合物谱型均具有极高的多样性。然而，目前学界对物种间表皮碳氢化合物谱型差异的成因，以及可能塑造该谱型的潜在选择压力，仍知之甚少。本研究针对蚂蚁的表皮碳氢化合物潜在选择压力展开了系统性探究。我们验证了两项假说：一是与其他物种形成共生关系（例如同巢共居（parabiosis）），二是蚂蚁栖息地的气候条件，均会对表皮碳氢化合物的组成产生影响。我们对来自五大洲的37种弓背蚁属（Camponotus）物种开展了大规模比对分析。研究结果表明，与其他物种紧密共生的蚂蚁类群，其体内的碳氢化合物链长显著更长，且甲基支链烯烃与双烯烃的占比也显著高于非共生或松散共生的类群。与之相反，气候因素并未对其产生显著影响。本研究证实，适应其他物种的共生容忍需求，会极大地塑造蚂蚁的表皮碳氢化合物谱型。