The House Finch is closely related to the Cassin’s Finch and the Purple Finch. All three species are streaked, and the males of all three have red plumage. The House Finch, the most common and widespread of the three, typically has a red head, breast, and rump, but does not have red coloring on its brown back or wings. This helps to differentiate it from the other two. Female House Finches have blurrier streaks and grayer undersides than the other two species. The breast streaks do not converge in a central spot as on many sparrows. They lack clear white stripes on their heads. House Finches have longer tails and appear more slender overall, and also have slightly curved bills, in contrast to the straight bills found in the other two species. Like most finches, they have notched tails. There is considerable color variation among males, from pale yellow, to orange with bright red, this being the most common. Many but not all males reach mature plumage in their first year. The variation in color is related to diet.