20. Parrotfish
Parrotfish have a truly remarkable bedtime ritual. Each night, they secrete a mucous cocoon around their bodies before settling in to sleep among the coral reefs. This bubble acts as a protective barrier, masking their scent from nocturnal predators like moray eels.
By creating this unusual sleeping bag, parrotfish can rest peacefully, blending into their colorful underwater world. It’s a unique example of evolutionary ingenuity beneath the waves. BBC