Whale shark (Kaschibo / shutterstock.com)
Whale sharks (Rhincodon typus) are the largest living fish. They reach a length of 12 meters (39 feet). However, according to unconfirmed reports, much larger animals have been observed. The whale shark has a flattened head and a very large mouth with small, scalelike teeth. Its back and sides are gray to brown with white spots among pale vertical and horizontal stripes, and its belly is white. As a filter feeder, the shark eats plankton and small fish. Whale sharks are harmless to humans. On the IUCN Red List, they are classified as vulnerable.