One reason that kittens sleep so much is because a growth hormone is released only during sleep.
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Parrotfish make themselves a kind of mucus 'sleeping bag' which masks their smell from predators and keeps parasites away.
4
Sharks have been on the planet longer than trees.
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Crows living in some urban areas drop nuts into traffic to let the passing cars crush them, then they wait for the red lights to stop the traffic so they can grab and eat it.
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Parrot parents "name" their children with a signature call.
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Bats sleep 18-20 hours per day.
5
Dolphins can rapidly heal from extreme injuries, such as shark bites, and regenerate their original body shape.
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