There are approximately three chickens for every human on Earth.
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Parrot parents "name" their children with a signature call.
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Penguins have a gland above their eye that turns saltwater into freshwater.
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The cat brain weighs about 30g.
167
Cats recognise the voice of their owner, but never evolved to care.
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A koi fish, named "Hanako", was owned by several individuals over many years and lived to be 226 years old, dying in 1977.
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Cymothoa exigua is a type of parasite that enters through fish's gills, eats their tongue, and then replaces it.
6