Institute of Organismic and Molecular Evolution, Johannes-Gutenberg-University Mainz, Hanns-Dieter-Hüsch-Weg 15, 55128, Mainz, Germany.
Department of Animal Ecology and Tropical Biology, University of Würzburg, Biocentre - Am Hubland, 97074, Würzburg, Germany.
J Chem Ecol. 2019 Sep;45(9):741-754. doi: 10.1007/s10886-019-01099-9. Epub 2019 Aug 27.
A vital trait in insects is their cuticular hydrocarbon (CHC) profile, which protects the insect against desiccation and serves in chemical communication. Due to these functions, CHC profiles are shaped by both climatic conditions and biotic interactions. Here, we investigated CHC differentiation in the neotropical parabiotic ant species Crematogaster levior and Camponotus femoratus, which mutualistically share a nest. Both consist of two cryptic species each (Cr. levior A and B and Ca. femoratus PAT and PS) that differ genetically and possess strongly different CHC profiles. We characterized and compared CHC profiles of the four cryptic species in detail. Our results suggest that Cr. levior A, Ca. femoratus PAT and Ca. femoratus PS adapted their CHC profiles to the parabiotic lifestyle by producing longer-chain CHCs. At the same time, they changed their major CHC classes, and produce more alkadienes and methyl-branched alkenes compared to Cr. levior B or non-parabiotic species. The CHC profiles of Cr. levior B were more similar to related, non-parabiotic species of the Orthocrema clade than Cr. levior A, and the chain lengths of B were similar to the reconstructed ancestral state. Signals of both the parabiotic partner (biotic conditions) and climate (abiotic conditions) were found in the CHC profiles of all four cryptic species. Our data suggest that mutualisms shaped the CHC profiles of the studied species, in particular chain length and CHC class composition. Beside this, signals of the parabiotic partners indicate potential impacts of biotic interactions, via chemical mimicry or chemical camouflage.
昆虫的一个重要特征是其表皮碳氢化合物 (CHC) 谱，它可以保护昆虫免受干燥，并在化学通讯中发挥作用。由于这些功能，CHC 谱受气候条件和生物相互作用的影响。在这里，我们研究了互惠共生的新热带拟态蚂蚁物种 Crematogaster levior 和 Camponotus femoratus 的 CHC 分化，它们共同分享一个巢穴。这两种蚂蚁都由两个隐种组成（Cr. levior A 和 B 以及 Ca. femoratus PAT 和 PS），它们在遗传上有所不同，并且具有强烈不同的 CHC 谱。我们详细地描述和比较了这四个隐种的 CHC 谱。我们的结果表明，Cr. levior A、Ca. femoratus PAT 和 Ca. femoratus PS 通过产生更长链的 CHC 来适应共生生活方式。同时，它们改变了主要的 CHC 类别，与 Cr. levior B 或非共生物种相比，产生了更多的链烯和甲基支链烯烃。Cr. levior B 的 CHC 谱与 Orthocrema 分支的相关非共生物种更为相似，而 Cr. levior A 的 CHC 谱与非共生物种更为相似，B 的链长与重建的祖先状态相似。共生伙伴（生物条件）和气候（非生物条件）的信号都存在于所有四个隐种的 CHC 谱中。我们的数据表明，共生关系塑造了所研究物种的 CHC 谱，特别是链长和 CHC 类别的组成。除此之外，共生伙伴的信号表明生物相互作用可能通过化学模拟或化学伪装产生潜在影响。
