Unsinkable Sam (nickname of a German ship's cat) who served on 3 warships, one German, two British, all sank in action. The cat survived each sinking, floating away on wooden planks to rescue.
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It would take about 1,200,000 mosquitoes to fully drain the average human body of blood.
217
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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