The elephant brain weighs about 6,000g.
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The oldest known animal in the world was 'Ming' the 405 year old clam, discovered in 2007.
492
A cat rubs against people not only to be affectionate but also to mark out its territory with scent glands around its face. The tail area and paws also carry the cat's scent.
293
Nervous dogs wag their tails to the left, and happy dogs to the right (from the dog’s point of view) – and fellow canines pick up on this lop-sided tail language.
10
Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12