By Susan Milius
Some of the scariest poop in Antarctica comes from an all-female invader species about the size of an ant. Researchers are now fretting about what the waste from these debris-eating midges may do to the continent’s once nutrient-sparse moss banks.
The midge Eretmoptera murphyi, a kind of tiny fly that can’t actually fly, hitchhiked onto the Antarctic island of Signy probably sometime in the 1960s during plant-introduction experiments that would never be allowed today. In moss banks where the alien midges now thrive, their excretions boost nitrogen concentrations to levels similar to those where seals come ashore, says Jesamine Bartlett, a polar and alpine ecologist at the University of Birmingham in England.