Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
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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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A newborn Chinese water deer is so small, it can (almost) be held in the palm of a hand.
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Some lizards, in which the tail is a major storage organ for accumulating reserves, will return to a dropped tail after the threat has passed, and will eat it to recover part of the sacrificed supplies.
13
It's possible to train your cat to use the toilet as a litter box and even flush afterwards.
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