Cartilaginous fish are a group of fish that have skeletons made of cartilage instead of bone. This group includes species like sharks, rays, and skates. Their flexible skeletons allow them to be agile swimmers, and they often have unique features like sharp teeth and specialized fins. These fish are found in oceans around the world and play important roles in marine ecosystems. Many cartilaginous fish, such as the great white shark, are top predators, helping to maintain the balance of ocean life. They also have a keen sense of smell and can detect prey from great distances.