The domestic duck (Anas platyrhynchos domesticus) is a subspecies of mallard that has been domesticated and raised for meat and eggs. A few are kept for show, as pets, or for their ornamental value. Almost all varieties of domesticated ducks, apart from the domestic Muscovy duck (Cairina moschata), are descended from the mallard, which was domesticated in China around 2000 BC.
Duck farming is simplified by their reliable flocking behaviour, and their ability to forage effectively for themselves. Over 80% of global duck production is in China. Breeds such as White Pekin are raised for meat, while the prolific Indian Runner can produce over 300 eggs per year. In East and Southeast Asia, polycultures such as rice-duck farming are widely practised: the ducks assist the rice with manure and by eating small pest animals, so that the same land produces rice and ducks at once.
In culture, ducks feature in children's stories such as The Tale of Jemima Puddle-Duck, and in Sergei Prokofiev's musical composition Peter and the Wolf; they have appeared in art since the time of ancient Egypt, where they served as a fertility symbol.