Synchronized evolution of the chemical signature of Reticulitermes Endogenous synchronization of the chemical signature of Reticulitermes (Isoptera, Rhinotermitidae) worker termites
Résumé
Termites of the genus
Reticulitermes
are characteristic of temperate regions. Their colonies
comprise various castes, the most numerous being that of workers which can develop into soldiers
or secondary reproductives (neotenics). Each caste has a mixture of hydrocarbons (HCs) on the
cuticle forming a chemical signature. The primary aim of this study was to compare the changes
in the chemical signature of a population of worker termites fed on paper with juvenile hormone to
differentiate them into soldiers with a control population of termites fed only on paper or wood for
one month. Gas chromatography was used to analyze the cuticular profi les of
Reticulitermes fl avipes
termites to determine whether they changed, and, if so, when and how. The data collected over one
month showed that the workers fed with JH did not differentiate into soldiers but that there were
progressive changes in the hydrocarbon profi le independent of the treatment. These results indicate
that the differentiation of the chemical signature of the worker caste is a dynamic process, depending
only on time and not on colony membership, confi rming that, for these termites, this signature has
a lesser role in colony membership than caste membership, unlike the chemical signatures of other
social insects. The temporal process of this cuticular change is also associated with a change in the
alkene / methyl-branched alkane ratio