Trembler

Tremblers are a New World group of passerine birds related to mockingbirds and New World catbirds. Like these, they are in the Mimidae family. There are 2-4 species in one genus, Cinclocerthia:

Among the living birds, they are apparently most closely related to the pearly-eyed thrasher.

Their common name comes from their peculiar behavior: if excited, they will show a much more exaggerated version of the wing-flicking also seen in other mimids, for example the northern mockingbirds. The tremblers do not just flick their wings, but shake their entire bodies in a trembling motion.