The blue whale is the largest animal ever to live on the earth, it's tounge weighs as much as an elephant, it's heart as big (and heavy) as a car and some of it's veins big enough to swim through!
The skull Pictured left is 19 feet long! Just on the right of the skull is an ordinarily sized man.
Blue whales feed almost exclusively on krill. They eat 4 to 8 tons (3.6 to 7.3 tonnes) of krill per day. Blue whale hunting was banned in 1966 by the International Whaling Commission and illegal whaling by the USSR finally halted in the 1970s, by which time 330,000 blue whales had been caught in the Antarctic, 33,000 in the rest of the Southern Hemisphere, 8,200 in the North Pacific, and 7,000 in the North Atlantic. "The largest original population, in the Antarctic, had been reduced to 0.15% of their initial numbers".
The Blue Whale is the biggest animal known on the Earth. It can grow up to a massive 100 feet (that's 30 METRES!) it also weighs more than 200 tons (181 tonnes)!