Shark species, biology, and famous encounters.
Test your knowledge with these top questions!
Which shark swims hundreds of miles up rivers into freshwater lakes?
Bull sharks regulate their body salts, letting them cruise far up rivers like the Amazon and Mississippi.
Sharks patrolled the seas long before which of these appeared?
Sharks predate dinosaurs by roughly 200 million years, and jellyfish were swimming even earlier.
A shark's skeleton is made entirely of what material?
Cartilage is lighter than bone and decays quickly, so fossil sharks leave behind mostly teeth.
What is the largest fish in the ocean?
Blue whales are bigger, but they are mammals; the plankton-filtering whale shark is the largest true fish.