English sparrow or house sparrow, small bird, Passer domesticus, common throughout most of the world. English sparrows are 4 to 7 in. (10–18 cm) long, with short, stout bills. The male is brown with black streaks above, grayish white below; it has white cheek patches and a black bib from bill to chest. The female is dull brown above and brownish white below. English sparrows are highly gregarious birds found in cities and settled rural areas; they are rarely seen away from human habitation. Chiefly seedeaters, they are agricultural pests, but they also eat insects that are harmful to crops. The house sparrow builds messy nests of grass and debris almost anywhere—under eaves, in drains, and in ventilator holes—and this has contributed to its reputation as an undesirable bird. It is extremely prolific, raising at least two broods a year; the clutch consists of four to seven olive-speckled white eggs. Native to the Old World, the bird was first introduced into the United States about 1850 to combat cankerworms, and it rapidly became widespread. Aggressive as well as prolific, it has largely replaced many native birds in urban areas. Unlike the native North American species called sparrows, which belong to the finch family, the English sparrow is a member of the Old World weaverbird family. It is classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Passeriformes, family Ploceidae.