In species of animals that are monogamous and have extensive bi-parental investment, both males and females are predicted to exhibit choosiness when selecting a mate (Shellman-Reeve 1999). During the swarming season, termites seek their life-time partners and together they found a new colony. Mate selection occurs during the short period when termites form tandem pairs on the ground. We investigated whether termites choose their partners according to physical parameters (size, weight) and/or according to genetic relatedness (promoting inbreeding or outbreeding). We collected alates of the Formosan subterranean termite, Coptotermes formosanus Shiraki, from five swarm clouds in the French Quarter, New Orleans, La. Alates from each swarm cloud were observed in arenas and 20 tandem pairs were collected and preserved in 100% EtOH; for each individual, sex, weight and head width were determined and genetic analysis was performed. Results show that paired males had a significantly larger head width than males that were not in tandem with females, i.e., larger males tend to pair sooner. We also found positive correlations in weight between the partners as well as in head width, i.e., heavier/larger males tend to pair with heavier/larger females. These findings indicate mate choice using physical parameters (or other factors associated with size) as cues. We are currently in the process of determining genetic relatedness between paired termites using microsatellite genotyping in order to study whether termites choose their mates according to relatedness (inbreeding vs. outbreeding) or if they mate randomly during colony foundation.

Shellman-Reeve, J. S. 1999. Proc. R. Soc. Lond. B. 266: 137-144.