Overview
- Published November 17 in Current Biology, the study documents Lasius orientalis and L. umbratus queens engineering the killing of a host queen by her own workers.
- In lab tabletop colonies, invaders first acquired the host colony’s odor, which allowed them to approach the resident queen without immediate attack.
- The parasitic queen then repeatedly sprayed the host queen, provoking workers to assault and ultimately kill their mother.
- Takeovers varied by species and effort: L. umbratus sometimes induced fatal attacks with two sprays in half a day, whereas L. orientalis delivered up to 16 sprays over 20 hours, with the queen dying days later.
- Researchers suspect the spray is formic acid and plan tests with synthetic formic acid to confirm causation, noting that acceptance of the parasite and her brood is not guaranteed after the queen’s removal.