Blue whale arteries are large enough for humans to swim through and their hearts are the size of cars.
12
When dragonflies mate, their tails form a love heart.
22
Sergeant Stubby was the only war dog to be promoted to sergeant through combat in WWI. He saved his regiment from surprise mustard gas attacks, found and comforted the wounded, and even once caught a German spy by the seat of his pants, holding him there until American Soldiers found him.
16
The elephant brain weighs about 6,000g.
274
It has been estimated that a bite from a grizzly bear can crush a bowling ball.
11
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
Dogs have been man's pet for over 14,000 years.
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