These are all of the fish in the filter-feeding group. On the top, you can see the Whale Shark (The largest living fish in the world). In the middle, you can see the Basking Shark (The second-largest live fish in the world). On the bottom, you can see the Megamouth Shark, a rather mysterious shark that has only been known to exist since November 15, 1976.
Here is a comparison between a human, a Whale Shark, and Basking Shark.
Here you can see the largest Whale Shark recorded compared to a school bus! The average size of adult whale sharks is estimated at 9.8 meters (32 ft) and 9 tons (20,000 lb).