The tits, chickadees, and titmice comprise Paridae, a large family of small passerine birds which occur in the northern hemisphere and Africa. Most were formerly classified in the genus Parus.These birds are called "chickadees" (onomatopoeic, derived from their distinctive "chick-a dee dee dee" communication or alarm call) or "titmice" in North America, and just "tits" in the rest of the English speaking world.