Outnumbered: a new dominant ant species with genetically diverse supercolonies in Ethiopia
A Lepisiota (Hymenoptera: Formicidae: Formicinae) species in Ethiopia has been observed forming supercolonies spanning up to 38 km. L. canescens occurs at very high densities where there is sufficient moisture or herbaceous cover and dominates the local ant community, traits reminiscent of an invasive species. The supercolonies are genetically diverse, however, indicating they have not gone through the population bottleneck usually characteristic of species invasions. We conclude that the species is native to this region, though expanding its range locally into areas of human disturbance, where it is exploding in numbers. The lack of aggression across a genetically diverse population suggests that mitochondrial genetic variation is decoupled from variation relating to colony recognition cues like cuticular hydrocarbons. All in all, L. canescens could have the makings of an invasive species at an international scale and may represent a novel system to study the evolution and spread of supercolonies in ants.
KeywordsAggression Church forest mtDNA Cytochrome oxidase I Invasive ant syndrome Recognition Unicolonial
The authors would like to thank the following people for assistance during this project: Harold Heatwole, Peter Hawkes, Gernot Kunz, Tegistu Adane, Addisu Osman, Barbara Thorne, Rob Plowes, Kate Parr, Brian Taylor, Stefan Cover, Nick Haddad, Robert R. Dunn and the Dunn Lab. This project received funding from the TREE (Tree Research, Exploration and Education) Foundation, the Southeast Climate Science Center, and the National Science Foundation (NSF-CAREER Nr. 09533390). Molecular sequencing was supported by The University of Tulsa faculty startup of WB.
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