House Sparrow

Male: a gray cap down the center of the head, a broad chestnut wrap from the eye around the nape, a clean pale-gray cheek, and a black bib under the chin that spreads wider in spring. Female: plain warm buff-brown, no bib, with a soft pale line behind the eye — a quieter look entirely.

That black bib is a rank badge — bigger bibs mean older, more dominant males, and the others read it like a name tag without a squabble. They don't really sing, either; they just cheep — a sparrow that chats instead of sings. And they'll raise a brood in a gas-pump nozzle, a traffic light, or a big-box-store sign without blinking.