Title: | Cuticular hydrocarbon profiles differ between ant body parts: implications for communication and our understanding of CHC diffusion |
Author(s): | Sprenger PP; Gerbes LJ; Sahm J; Menzel F; |
Address: | "Institute of Organismic and Molecular Evolution (iomE), Johannes Gutenberg-University Mainz, Hanns-Dieter-Husch-Weg 15, Mainz, 55128, Germany. Department of Evolutionary Animal Ecology, University of Bayreuth, Universitatsstrasse 30, Bayreuth, 95477, Germany" |
ISSN/ISBN: | 1674-5507 (Print) 2396-9814 (Electronic) 1674-5507 (Linking) |
Abstract: | "Insect cuticular hydrocarbons (CHCs) serve as communication signals and protect against desiccation. They form complex blends of up to 150 different compounds. Due to differences in molecular packing, CHC classes differ in melting point. Communication is especially important in social insects like ants, which use CHCs to communicate within the colony and to recognize nestmates. Nestmate recognition models often assume a homogenous colony odor, where CHCs are collected, mixed, and redistributed in the postpharyngeal gland (PPG). Via diffusion, recognition cues should evenly spread over the body surface. Hence, CHC composition should be similar across body parts and in the PPG. To test this, we compared CHC composition among whole-body extracts, PPG, legs, thorax, and gaster, across 17 ant species from 3 genera. Quantitative CHC composition differed between body parts, with consistent patterns across species and CHC classes. Early-melting CHC classes were most abundant in the PPG. In contrast, whole body, gaster, thorax, and legs had increasing proportions of CHC classes with higher melting points. Intraindividual CHC variation was highest for rather solid, late-melting CHC classes, suggesting that CHCs differ in their diffusion rates across the body surface. Our results show that body parts strongly differ in CHC composition, either being rich in rather solid, late-melting, or rather liquid, early-melting CHCs. This implies that recognition cues are not homogenously present across the insect body. However, the unequal diffusion of different CHCs represents a biophysical mechanism that enables caste differences despite continuous CHC exchange among colony members" |
Keywords: | Formicidae cuticle regionalization eusocial insects melting temperature nestmate recognition pheromones; |
Notes: | "PubMed-not-MEDLINESprenger, Philipp P Gerbes, Lisa J Sahm, Jacqueline Menzel, Florian eng England 2021/10/08 Curr Zool. 2021 Feb 11; 67(5):531-540. doi: 10.1093/cz/zoab012. eCollection 2021 Oct" |