Octopuses change color to camouflage themselves from predators such as stingrays and eels. Octopuses have even been observed changing color in their sleep. Octopus's color-changing ability is known as ...

Octopuses can flip from mottled rock to smooth sand in less time than it takes a human to blink, yet their eyes carry only a single visual pigment that should make them functionally colorblind. The ...