Who: Prof Kazuki Tsuji, University of the Ryukyus, Okinawa, Japan
Where: JCU Townsville NS 002 (TSV) and B1-031 (CNS)
When: Thursday, 29th October 2009 1.00pm – 2.00pm
Recently Ohtsuki and Tsuji (2009) has proposed a new hypothesis on the mechanism of evolution of worker policing in social Hymenoptera, which assumes simultaneous operation of intracolonial conflicts over sex allocation, male parentage, and reproductive allocation. A novel prediction of this model is that worker policing will depend on the stage of colony growth and under queen single mating strong worker policing will occur only at the ergonomic stage. In this seminar I will talk about two issues related to this hypothesis. First, I show data strongly supporting Ohtsuki and Tsuji’s prediction in the ponerine ant Diacamma sp. Second, I suggest a proximate mechanism of colony size related behavioral regulation in this ant that is achieved though individual contacts. This is a pioneering study revealing an explicit colony size “sensing” mechanism in social insects.