ANDRZEJ KRAUZEIn the famous case of Darwin’s finches, natural selection acts decisively, elevating a trait in the population, weeding it out, or simply ignoring it. But in actuality, natural selection can sometimes exert a more complicated influence. An unusual pattern of genetic selection turns out to be responsible for the rampant spread of the invasive Asian honeybee (Apis cerana) from Papua New Guinea into Australia, a pattern that Rosalyn Gloag of the University of Sydney and her colleagues have managed to decode.
The first Asian honeybees reached Australian shores in 2007, probably on the mast of a ship or stowed away in a shipping container. The bees made landfall in Cairns, a city on the continent’s northeastern coast, and spread rapidly from there. Bruce White, a retired government apiculture and biosecurity specialist, says that Australian officials who responded to the invasion were ill equipped to contain the bees and did not realize how quickly colonies could disperse. Concerned beekeepers alerted authorities to A. cerana hives that appeared in their yards, but the eradication effort proved futile.
Up until now, the success of A. cerena in Australia has posed something of a biological puzzle. Under the normal rules of evolution, the invasive bees should have been hamstrung by ...
