Sharks: they rule 70 percent of the world | Photo: Elias Levy/Creative Commons

Sharks are one of the oldest living species on planet earth. They've survived the most severe mass extinction events, and they rule 70 percent of the world.

Ready to learn things you didn't know about sharks? You will be amazed by how special sharks really are. Sharks are fast and intelligent, and they can only fear humans. Yes, we are their only predators.

But their body is a complete underwater machine. Their smell, sight, hearing, mouth, skin, electroreception and lateral line is a complex system built to survive and hunt in multiple environments.