REGULATION OF THE CHEMICAL SIGNATURES OF 2 TERMITE SPECIES, RETICULITERMES-SANTONENSIS AND RETICULITERMES-LUCIFUGUS GRASSEI, LIVING IN MIXED EXPERIMENTAL COLONIES

Each of the two termite species Reticulitermes santonensis and Reticul itermes lucifugus grassei has its own distinct chemical signature, on which the intra- and inter-species recognition processes are based. Wh en the 2 species were kept together in artificially mixed colonies, ch anges in their chemical signatures were observed after only 2 h of coh abitation: each species acquired all the hydrocarbons specific to the other species, but R. lucifugus grassei acquired larger amounts of the R. santonensis hydrocarbons than vice versa. After a 24 h period of c ohabitation, both the homospecific and allospecific signatures carried by all the individuals were in the same proportions as those characte rizing the individuals of the 2 species prior to cohabitation. The oth er species' signature was therefore acquired additively, probably via physical contacts between the cohabiting individuals. After 14 days of cohabitation, however, changes in the amounts of some of the componen ts synthesized by each species were observed, and the allospecific sig nature also differed from that acquired at the beginning of the experi ment: a regulatory process involving quantitative changes in only some of the cuticular components was therefore at work. The results obtain ed with this artificially mixed colony model show that the hypotheses put forward up to now by previous authors about regulatory mechanisms of this kind are not in fact mutually exclusive, but may be applicable to various successive periods of cohabitation.