The blue whale is the largest mammal on the planet. Its tongue alone weighs as much as an elephant, and when it opens its mouth, up to 90tonnes of water can fit into it. It also has the biggest heart in the world, weighing 180kg and making it about as large and heavy as a gorilla. Fun fact When the blue whale blasts water through its blowhole, it creates a 9-m-high fountain. Dimensions: 10.79 x 3.98 x 1.93 inch(W x D x H) AGES: 3+ years