Agent-based Model to Explore the Stability of Social Insect Symbiosis

Symbiosis is prevalent throughout biology, including between social insects. One such instance is the Sceptobius lativentris rove beetle evolving to coexist stably with Liometopum occidentale using acquired cuticular hydrocarbon (CHC) mimicry, with no known instances of a beetle leaving its colony and assimilating into nearby ant colonies. With that in mind, how do beetles and ants interact to maintain this stable coexistence? To better understand this, we employed an agent based model of beetle ant interactions to explore how their dynamics limit the beetle to within its host colony. We found that various negative feedback loops exist. For example, an extremely low host ant population allows colony crossings to occur, but leaves beetles vulnerable to neighbor hostility, making crossings less likely overall. Furthermore, crossings can occur with extremely close neighboring colonies, but the increased fighting also makes the arrangement unstable and unlikely. The conflicting effects of several parameters create a stable beetle-ant system and allow for long term symbiotic evolution. We believe that these results are a crucial clue in understanding insect evolution and the dynamics of insect populations in general.