Common Cuttlefish

A master of disguise with green blood and three hearts/Marine Life

The common cuttlefish (Sepia officinalis) is a cephalopod famous for its extraordinary camouflage abilities. Up to 45 cm in mantle length and weighing about 4 kg, it can change the color, pattern, and even texture of its skin in milliseconds using millions of chromatophore cells. It has three hearts, blue-green blood, a W-shaped pupil, and the highest brain-to-body ratio of any invertebrate. Its internal shell (the cuttlebone) is commonly given to pet birds as a calcium supplement.