The Blue Whale (Balaenoptera musculus) is the earth's largest animal. It eats 4 to 8 tons (3.6 to 7.3 metric tons) of krill (shrimp-like creatures) per day. In the wild, the average lifespan is 80 to 90 years. This magnificent marine mammal reaches up to 100ft (30 m) in length and weighs around 200 tons (181 metric tons). Their tongues can weigh as much as an elephant, and their hearts are as heavy as cars. Blue Whales are baleen whales, meaning that instead of teeth, they have fringed plates that act as a sieve when feeding, expelling the vast quantities of water taken in while trapping krill.

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