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

• Grey trembler (Martinique trembler), Cinclocerthia (gutturalis) gutturalis
  • Saint Lucia trembler, Cinclocerthia (gutturalis) macrorhyncha
• (Southern) brown trembler, Cinclocerthia (ruficauda) ruficauda
  • Northern brown trembler, Cinclocerthia (ruficauda) tremula

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 such as the northern mockingbirds. The tremblers do not just flick their wings, but shake their entire bodies in a trembling motion.