In for the Kill All animals give off electric signals through their muscles and nerves. Sharks can pick up these signals through small holes on their snouts. It’s called electroreception. Sharks, the duck-billed platypus of Australia, and a few other animals are thought to have this sense. A shark could pick out a single heartbeat
This seal leaps out of the way to avoid the great white shark.
from 1 meter away. So even with his eyes closed, this shark knows exactly where his prey is. T e shark’s jaws snap shut. T ey
narrowly miss the seal. T e seal dives back into the water to get away. T e shark follows. He opens his mouth
Making His Move He is swimming low in the water now. A small cluster of young seals is splashing above him. Blood oozes from one pup’s tiny scratch. T at’s what the shark has been smelling. T is seal is the perfect prey for him. Young seals have less experience defending themselves against predators. It’s time for the shark to make his move.
He pushes forward with his back fin and gathers speed as he nears the group. Suddenly, he springs up, breaking the
surface of the water. He opens his mouth, revealing rows of jagged teeth. T e injured seal leaps out of the water to avoid the shark. In mid-air, the seal turns back. He swipes at the great white’s eyes with his sharp claws. T e great white rolls his eyes backward to protect them. But he can still “see” by using another one of his senses.
again, and his jaws move forward as his head moves back. T e lower jaw strikes first, stabbing the seal. T en the upper jaw clamps down. He holds the seal locked in his jaws
and shakes his head from side to side. T e shark’s teeth work like rows of small saws. Aſt er he finishes his meal, the great white moves on. It may be weeks before he needs to eat again.
WORDWISE cartilage: a hard, fl exible material that makes up a shark’s skeleton
electroreception: a way sharks have of finding other animals by detecting the electric signals they send out
lateral line: a system of tiny tubes under a shark’s skin that help it detect movement
olfactory bulb: an organ a shark uses with which to smell
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