Chaetae are bristle-like structures found on the bodies of certain invertebrates, particularly annelids such as earthworms. These structures are made of chitin and serve various functions, including locomotion and anchoring the organism to surfaces. In addition to annelids, chaetae can also be found in some arthropods and mollusks. They help these animals move through their environments by providing grip and stability, allowing them to navigate different terrains effectively.