A gene which helps a harmless African butterfly ward off predators by giving it wing patterns like those of toxic species, has been identified by scientists who publish their findings today (20 February 2008). The mocker swallowtail butterfly, Papilio dardanus, is unusual because it emerges from its chrysalis with one of a large number of different possible wing patterns and colours. This is different from most butterfly species which are identified by a common wing pattern and colour. Furthermore, some of the different patterns that the mocker swallowtail exhibits mimic those of poisonous species, which affords this harmless insect a valuable disguise which scares off predators.