They can match the colors and even textures of their surroundings, allowing them to hide in plain sight. Octopuses are highly intelligent animals, masters of camouflage that have evolved an array of tricks over tens of millions of years to avoid or thwart would-be attackers. “Cephalopod” is Greek for “head-foot,” which makes sense, since their limbs are attached directly to their head.

They have bulbous heads, large eyes, and eight very useful arms. Octopuses (or octopi, if you prefer) are cephalopods, invertebrates that also include squid and cuttlefish. Current Population Trend: Unknown What are octopuses?