Author
PENICK, CLINT - Arizona State University | |
TROBAUGH, BETH - Arizona State University | |
Brent, Colin | |
LIEBIG, JUERGEN - Arizona State University |
Submitted to: Journal of Insect Behavior
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 4/5/2012 Publication Date: 4/27/2013 Citation: Penick, C.A., Trobaugh, B., Brent, C.S., Liebig, J. 2013. Head butting as an early indicator of reproductive disinhibition in the termite zootermopsis nevadensis. Journal of Insect Behavior. 26:23-24. Interpretive Summary: In lower termites, functionally sterile larval helpers are capable of becoming reproductively active with the loss of their colony’s king or queen. This transition takes several weeks, but probably starts shortly after colony members detect when a reproductive-specific signal is missing. We investigated the early response of termite helpers to the removal of their king and queen in the primitive termite species, Zootermopsis nevadensis. Within 6-12 hrs after reproductives were removed, helpers displayed an increase in head-butting, a behavior associated with dominance in other termite species as well as in closely related roaches. Head-butting also increased with the loss of just the king or queen. We did not find evidence, however, that this response was gender-specific: males and females were equally likely to increase head-butting no matter the gender of the reproductive that was removed. Finally, we discovered that reproductive-specific compounds present on the cuticle of king and queen termites were also present in their feces, although these did not seem sufficient to inhibit the increased head-butting after the reproductives were removed. Collectively, the results indicate that non-reproductive termites are highly attuned to changes in reproductive-specific cues, and suggest an alternative means by which reproductives can signal their presence throughout the colony. Technical Abstract: In lower termites, functionally sterile larval helpers are totipotent, capable of becoming reproductively active with the loss of their colony’s king or queen. Full reproductive development may take several weeks, but initiation of this response most likely occurs shortly after colony members detect when a reproductive-specific signal is missing. We investigated the early response of termite helpers to the removal of their king and queen in the basal termite species Zootermopsis nevadensis. Within 6-12 hrs after reproductives were removed, helpers displayed an increase in head-butting, a behavior associated with dominance in other termite species as well as in closely related roaches. Head-butting also increased with the loss of just the king or queen. We did not find evidence, however, that this response was sex-specific: males and females were equally likely to increase head-butting no matter the sex of the reproductive that was removed. Finally, we discovered that reproductive-specific compounds present on the cuticle of king and queen termites were also present in their feces, although these did not seem sufficient to inhibit the increased head-butting after the reproductives were removed. Collectively, the results indicate that non-reproductive termites are highly attuned to changes in reproductive-specific cues, and suggest an alternative means by which reproductives can signal their presence throughout the colony. |