Pattern of recovery of species-specific cuticular hydrocarbon mixtures by Reticulitermes santonensis and Reticulitermes lucifugus grassei after being removed from a mixed group. Is the acquisition of allospecific hydrocarbons reversible?

Each of the termite species Reticulitermes santonensis and Reticulitermes lucifugus grassei has its own particular cuticular chemical profile. When members of the two species are placed together to form artificially mixed species groups, their chemical profiles undergo changes: Each species acquires all the hydrocarbons which initially characterized the other species. When the members of a mixed group which had been kept together for 24 h were slit into two homospecific groups, the cuticular profiles of the members of both groups immediately showed a sharp drop in both the homospecific and allospecific components. In R. santonensis, the homospecific hydrocarbons subsequently increased in quantity, reaching values which were higher on the 33rd day after the separation than those initially recorded in this species; whereas in R. lucifugus grassei, the homospecific hydrocarbon proportions were still lower on the 33rd day than the initial values. In both species, the allospecific hydrocarbon levels began to increase sharply on the 5th day after separation, and the homospecific products still showed no tendency to return to the initial proportions 33 days after separation. In the light of these results, some hypotheses are put forward as to what mechanisms might possibly regulate the hydrocarbon profiles of these two species.