The orbicularis oris and buccinator, the kissing muscles, pucker the mouth. The buccinator also flattens the cheeks, as when one whistles or blows a trumpet, and is sometimes called the trumpeter’s muscle. Smiling is accomplished primarily by the zygomaticus muscles. Sneering is accomplished by the leavator labii superioris, and frowning or pouting is largely caused by the depressor anguli oris.