The influence of social experience on the behavior of male cockroaches,Nauphoeta cinerea

Abstract

The influence of social experience on rates of agonistic behavior was investigated in a cockroach, Nauphoeta cinerea. Social experience was manipulated by establishing three types of groups of four identically aged males: (1) ran-domly chosen, socially naive males (control); (2) males of similar status and activity level (from treatment 1); and (3) males returned to their original hierarchy after experiencing treatment 2. In the control groups, we found stable hierarchies, significant differences in the rate of agonistic behaviors exhibited among different status males, and a significant relationship between social status and level of agonism. We also compare activity levels within and among groups after males had novel social experiences. Among similar status individuals, we found less activity than when they wereintheir original groups. When males were returned to their original groups, the level of activity increased compared to the level of activity before treatment. The social status of males was unstable after these treatments. Losing tended to result in relatively more subordinate behavior, and winning in relatively more dominant behavior by a male. Within groups, the rate of agonism also increased over 5 days in groups of males that had no previous interactions with each other, while the rate of agonism remained the same in groups of familiar males. We interpret these results in light of male-male assessment and the maintenance of social status in this species.