windandwater:

OCTOPUSES ARE COMING FOR US
Part 1: Mimic Octopus

(pulled from various articles, bolded emphasis always mine, sometimes edited for grammar/relevancy)

In the natural world , mimicking a more dangerous creature is a common strategy for avoiding predators. But there is only one animal that can dynamically mimic many different creatures—the incredible mimic octopus.

Having multiple acts benefits the octopus as predators are less likely to catch on to any individual one. If too many octopuses mimic a single creature—say, a lionfish—then predators are more and more likely to encounter the fake than the real deal.

Like all good performers, the mimic octopus caters to its audience. It only acts like a sea-snake when confronted by territorial damselfish, which are preyed upon by sea-snakes.

Their bodies lack any sort of protective shell or skeleton and they have had to evolve other incredible defenses to compensate. Soft bodies make them vulnerable, but they also make octopuses particularly well-suited to deception.

Without skeletons, they are expert contortionists, and can change shape or squeeze into tight spaces. Their remarkable skin can change texture, becoming spiky or smooth on a whim. It also contains sacs of pigment called chromatophores which can be expanded or contracted to produce rapid changes of colour and pattern. Armed with this arsenal of stealth, all octopuses are masters of disguise. (x)

Mimic octopuses have been observed shifting between impersonations as they cross the ocean floor to return to their burrows. (x)