If a vampire bat goes 2 days without drinking blood, they can die. However, well fed female bats will puke up blood and share it with other bats that they like in exchange for grooming.
13
In 1859, the largest known geomagnetic storm struck the Caribbean, causing an aurora and telegraphs could even operate without a power source.
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In 1518, a "dancing plague" struck Strasbourg, Alsace, whereby hundreds of people danced fervently in the streets over the period of a month. Some suffered heart attacks or strokes, and many others died from sheer exhaustion. It remains unexplained.
19
In 2011, there were 3 known cases around the world of twins coming from different fathers.
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