Breeding structure and invasiveness in social insects.

Plasticity in life history traits is commonly used to explain the invasion success of social insects. While intraspecific plasticity is often recognized, interspecific variability is easily overlooked, whereby different species exhibit different strategies. The presence of many queens per colony and the collapse of colony boundaries have favored invasiveness for many ant species. However, these strategies are absent from other successful social invaders. Here, we report that various life-history traits may differentially enhance the invasion success in social insects. We suggest that other aspects of their breeding system, like asexual reproduction, intranidal mating and pre-adaptation to inbreeding may enhance their invasion success. Thorough comparative studies between native and introduced populations or studies of closely related species will help identify additional traits favoring the invasion success of social insects, and ultimately provide a more comprehensive picture of the evolutionary factors enhancing invasiveness across this phylogenetically and ecologically diverse group. Published by Elsevier Inc.