Some older/less efficient worker termites will develop 'backpacks' of toxic chemicals that explode when the termite is threatened. They are essentially used as suicide bombers when the colony is being attacked.
8
A hippo sleeping underwater automatically rises to the surface every ~4 minutes and breathes without waking.
23
Penguins have a gland above their eye that turns saltwater into freshwater.
12
The oldest known animal in the world was 'Ming' the 405 year old clam, discovered in 2007.
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