House fly  (Musca domestica)

The house fly is, perhaps, the most common and widespread animal in the world (3). It is a serious pest, which spreads many disease-causing pathogens including Salmonella, anthrax and polio (4). It is greyish in colour with four dark stripes along the back (4). Like all flies it has one pair of membranous 'true' wings; the second pair of wings are modified into drumstick-like appendages known as 'halteres', which are used in balance. The sponge-like mouthparts are adapted for feeding on liquids, and the reddish compound eyes are large (5).