Male unit. The male House Sparrow has a grey crown, cheeks and underparts, black on the throat, upper breast and between the bill and eyes. The bill in summer is blue-black, and the legs are brown. In winter the plumage is dulled by pale edgings, and the bill is yellowish brown. The black throat patch on the males is variable in size, and the size of that patch or badge is correlated with the aggressiveness, suggesting that it is a signal to show dominance in a social situation. The female has no black on head or throat, nor a grey crown; her upperparts are streaked with brown. Common Name in Spanish: Gorrión Común