This octopus was discovered in 1998 off the coast of an Indonesian island, and is perhaps the greatest shape-shifter of all. Similar to the cuttlefish, it is capable of mimicking its background environment by changing the color and texture of its skin. However, it is the only animal able to mimic a diverse range of species—at least 13 have been recorded so far—including lion fish, sea snakes, jellyfish, and sea anemones.

Most of the impersonated species are poisonous, giving the mimic octopus protection from predators, but it is also known to imitate members of the opposite sex in crabs, luring them in before feasting on them. The mimic octopus has remarkable dexterity, being capable of changing its color, behavior, shape and texture, and can alter its mimicry according to the circumstances.

5. Pufferfish

pufferfish
Watch out, he’s about to puff!
Image: Benjamin Jakabek/Flickr, CC BY-NC-ND

Porcupinefish and pufferfish are a group of fish that puff themselves up rapidly when threatened. These fish can more than double their size by inflating their stomachs with water or air, making themselves much less attractive as a meal to predators—would you want to eat a large spiky ball?—and too large to be eaten by predators with smaller mouths.

Most porcupinefish and pufferfish also contain a deadly toxin, far more poisonous than cyanide, so if predators taken unaware usually won’t last for long. The meat from pufferfish is considered a delicacy in Japan, where it is carefully prepared by trained chefs, although it seems several customers still die each year.

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