Origin, behaviour, and genetics of reproductive workers in an invasive ant

Abstract Background Worker reproduction has an important influence on the social cohesion and efficiency of insect colonies, but its role in success invasive ants been neglected. We used observations 233 captive laboratory experiments, genetic analyses to investigate conditions for worker Anoplolepis gracilipes (yellow crazy ant) potential cost interspecific defence. determined prevalence production males whether it is triggered by queen absence; physogastric workers with enlarged abdomens are more likely be reproductive, how normal compare their contributions foraging defence; worker-produced that could have queen- or differ size heterozygosity. Results Sixty-six our colonies produced males, 25 these, some only workers. Colonies were produce especially queenless colonies. The average number days between first appearance eggs adult was 54.1 ± 10.2 (mean SD, n = 20). In experiment, removal increase proportion Physogastric yolky oocytes (37–54.9%) than (2–25.6%), which indicator fertile trophic egg production. less aggressive during aggression tests foraged head width wing length 4.0 4.3% greater respectively those undetermined source. Our microsatellite DNA indicate 5.5% 14.3% source heterozygous, suggests presence diploid and/or mosaics A. . Conclusions experimental work provides crucial information colony ability absence queens may also contribute as species if intranidal mating can take place virgin males.