LOSS OF INTRASPECIFIC AGGRESSION IN THE SUCCESS OF A WIDESPREAD INVASIVE SOCIAL INSECT

Despite the innumerable ecological problems and large economic costs a ssociated with biological invasions, the proximate causes of invasion success are often poorly understood. Here, evidence is provided that r educed intraspecific aggression and the concomitant abandonment of ter ritorial behavior unique to introduced populations of the Argentine an t contribute to the elevated population densities directly responsible for its widespread success as an invader. In the Laboratory, nonaggre ssive pairs of colonies experienced lower mortality and greater foragi ng activity relative to aggressive pairs. These differences translated into higher rates of resource retrieval, greater brood production, an d Larger worker populations.