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.
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An alligator can go through 2,000 to 3,000 teeth in a lifetime.
268
Shark corneas are used in eye transplants and shark bone marrow can be used to graft human bones.
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Alligator snapping turtles can live for over 150 years. Scientists know this because some of the turtles had musket balls in their stomachs.
271
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
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