Octopuses have 3 hearts.
Two pump blood to the gills, one to the body — and their blood is blue.
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Bananas are slightly radioactive.
They contain potassium-40 — totally harmless at normal levels.
Read this fact →Honey never spoils.
Archaeologists have found edible honey in ancient tombs.
Read this fact →Sharks existed before trees.
Sharks are older than many land ecosystems we take for granted.
Read this fact →Your brain uses ~20% of your energy.
Even at rest, it’s one of the body’s biggest energy consumers.
Read this fact →A day on Venus is longer than its year.
It rotates so slowly that it takes longer to spin than to orbit the Sun.
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