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There is a disease that, over time, converts your muscular tissue into bone
~9% of all humans who ever existed are still alive today.
The Soviet Union had a program in which they tried to train Dolphins to kill humans with weapons and destroy submarines with bombs.
There are more tigers in private collections in Texas than there are left in the wild.
Mike the Headless Chicken who lived without a head for two years. People think I'm making up an urban legend when I mention Miracle Mike.
There is a species of shark - the Greenland shark - that has a lifespan of up to 400 years
turkeys can spontaneously impregnate themselves through a process called Parthenogenesis
Since the current water speed record was set in 1978, everyone thats tried to beat it since has died.