Cuttlefish - Chameleon of the Sea
Also referred to as “the chameleon of the sea” because if its ability to alter its skin color at will, the cuttlefish is cephalopod that gets its name from the internal structure it possesses known as a “cuttle bone”. The cuttlebone is what differentiates the cuttlefish from its close relative the squid. The porous argonite structure exists to provide the cuttlefish with buoyancy (it does so by regulating the gas-to-liquid ratio within the body). Each cuttlebone has different a shape, size, texture, and ridge pattern; making no two specimens the same.
Cuttlefish possess some of the most developed eyes in the entire animal kingdom, and although technically color-blind, they can perceive the polarization of light. Their retinas have two spots of sensor-cell concentration; one which can look more forward, and one that looks more backward. Also, where most animals reshape their lens to focus, cuttlefish reshape their entire eye, and they have no blind spots because of their optic nerve's positioning. It's been speculated that the cuttlefish's eyes are fully developed before they're born and that they can observe their surroundings while still in the egg.
It has also been speculated that the cuttlefish prefer to hunt the prey they are exposed to before birth. They generally feed on crabs, fish, and shrimp using their camouflage to surprise prey before opening their eight arms so that their two tentacles can reach out and grab their meal. They can be found in the tropical waters along the eastern and southern coasts of Asia, western Europe, Africa, Australia, and the Mediterranean sea.