Because of its large size, several organs of the blue whale are the largest in the animal kingdom. A blue whale's tongue weighs around 2,700 kg (3 short tons) and, when fully expanded, its mouth is large enough to hold up to 9,000kg (99 short tons) of food and water. A female Asian elephant's average weight is also 2,700 kg. Their African counterparts are heavier: about 4,000 kg. And and still a couple of them could easily fit inside a blue whale.

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