Feeding Mechanism of Animals with Specialized Rasping Tongue Structure

What are animals that obtain food by scraping food particles off the substrate using a specialized rasping tongue structure?

Choose one:

A. Chitons

B. Hagfish

C. Sea Lampreys

D. All of the above

Answer:

D. All of the above

Animals such as chitons, hagfish, and sea lampreys scrape food particles off surfaces using a specialized rasping tongue structure or a similar organ called a radula.

Animals that obtain food by scraping food particles off the substrate using a specialized rasping tongue structure are mainly found within the group of animals known as Polyplacophora, commonly referred to as chitons. These marine animals have a unique feeding organ called a radula, which they use to scrape food organisms off rocky surfaces. The radula has teeth composed of ultra-hard magnetite, proven to be extremely hard and stiff.

For example, chiton teeth are as much as three times harder than human enamel and the calcium carbonate-based shells of mollusks. Not only chitons but also species like Pacific hagfishes and parasitic sea lampreys use similar methods of food collection. Instead of a radula, they use their rough tongues to rasp away their food.