Sharks

• Sharks don't get infections.
• Sharks have no bones except in their teeth and jaws.
• Most fish see colors, but sharks don't.
• The skin of a female shark is thicker than the skin of a male shark.
• Nine species of shark have been known to kill humans: white, bull, tiger, hammerhead, lemon, whitetip, mako, dusky, and blue.
• Some fish can stop suddenly in the water, but sharks can't.
• Some sharks lay eggs, but most sharks give birth to live pups.
• Lots of beasts die when they lose their teeth. Not the shark. It may go through 20,000 teeth in its lifetime, replacing them along the way. This has much to do with why the shark is a special sort of monster.
• Sharks wave their heads from side to side as they swim because they are smelling the water. The nostril that gets the strongest odor points them in the direction of their prey.
• Sharks can hear the heartbeats of other fish.
• Two-thirds of a shark's brain works solely on odors.
• The shark is the only marine animal that doesn't sleep at all.
• Its liver is the only place a shark stores its fat.