Dolphins sometimes have fun by blowing bubbles and creating rings of air underwater, which they then swim through.
17
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.
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A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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Urechis unicinctus is a species of marine spoon worm that is widely referred to as the ‘penis fish’.
2
During World War 1, starving wolves amassed in such great numbers that Germans and Russians had a temporary cease fire to fight off the wolf attacks.
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