THE ROLE OF CUTICULAR HYDROCARBONS IN INSECTS, pp. 91-114
Authors: Falko P. Drijfhout, Ricarda Kather ,Stephen J. Martin, School of Physical and Geographical Sciences, Keele University, Keele, UK, and others
Abstract: Cuticular hydrocarbons are present on the surface of all insects and play an important role in the life of insects. Although primarily anti-desiccation agents, cuticular hydrocarbons are emerging as important chemicals in insect communication. Here we discuss the usefulness of hydrocarbons both as waterproofing and signalling compounds. The three major groups of hydrocarbons, i.e., n-alkanes, alkenes and methyl branched hydrocarbons, are discussed in detail. The biosynthesis of these cuticular hydrocarbons is briefly outlined as well as the role of cuticular hydrocarbons in taxonomy. In many non-hymenoptera insect studies, a simpler cuticular hydrocarbon profile has allowed researchers to identify the role of certain compounds, and the various functions of these are not spread evenly across the various groups of hydrocarbons. Due to the general complexity of many insect cuticular hydrocarbon profiles, which can contain upwards of 100 compounds, comparisons between groups are normally based on the entire profile using multi-variant statistical methods. Here, we highlight potential problems with the detection and analysis of cuticular hydrocarbons. By drawing information across a wide spectrum of studies it appears clear that the main role of the n-alkanes is to control trans-cuticular water movement while the unsaturated compounds and methyl-branched hydrocarbons are more likely to be involved in communication. If future studies can concentrate on determining initially which groups of cuticular hydrocarbons are of interest, it would help narrow down the search for the exact role of hydrocarbons in insect societies. This comprehensive introduction to cuticular hydrocarbons is aimed at the rapidly increasing number of scientists, especially biologists, who are studying the role of cuticular hydrocarbons in insect behaviour.