References and Further Information: 1  Morrissey, J.F. and J.L. Sumich. 2012. Introduction to the Biology of Marine Life (10th Edition). 2  University of California Museum of Paleontology. Bilateral (left/right) Symmetry.
A lot of things. For one, Whale sharks are fish and use gills to breathe. Blue whales are mammals. The blue whale is also bigger than the whale shark. The tail structure is also different if you watch the whale shark swim, it uses its tail in a side to side motion while the blue whale uses a up and down movement.
Species: musculus. Blue whales are the largest baleen whale species--in fact they are the largest animal in the world. Blue whales can grow to be about 100 feet (30.5 meters) in length and may weigh around 160 tons.They are mottled bluish gray, with broad flat heads and a small dorsal fin located in the last forth of the body.pecies: musculus. Blue whales are the largest baleen whale species--in fact they are the largest animal in the world. Blue whales can grow to be about 100 feet (30.5 meters) in length and may weigh around 160 tons.