Whales to the Rescue: How Whales Help Engineer the Planet

Whales to the Rescue: How Whales Help Engineer the Planet — page 5
WHALES OF THE WORLD Whales are among the largest animals on the planet and the blue whale is the largest animal ever to have lived on Earth Its tongue is as heavy as two hippos and its heart is so big a ten year old could fit inside it with her arms stretched wide There are ninety known species of whales dolphins and porpoises in the world Scientists call these animals cetaceans Although they vary in size a harbor porpoise could fit in your bathtub while a fin whale is about as long as a tennis court cetaceans all have a similar appearance Their smooth torpedo shaped bodies help them slip easily through the water A muscular tail gives thrusting power and they steer with paddle like flippers They breathe through either one or two blowholes the number varies between groups on top of their heads Whale Dolphin or Porpoise Dolphins and porpoises are smaller than most whales and are often seen zipping and leaping through the sea Although their looks can vary most dolphins have a pointy beak In contrast porpoises have a blunter snout