What is the color of an octopus blood? Did You Know? Snails, spiders and octopi have something in common- they all have blue blood! We’re not talking in the sense of royalty, these creatures literally have blue blood.
Do squid have green blood? The blood of octopuses and squids is blue because they use a different protein for oxygen transport than human beings do. This protein, hemocyanin, relies on copper to bind with oxygen, which causes the blood’s discoloration.
Do squid have copper-based blood? Meanwhile, all the octopus and squid species are ocean-dwelling creatures, living from the tropics to the temperate zones. The protein in copper-based blood, called hemocyanin, functions better than iron-based hemoglobin would in carrying oxygen through the mollusks’ bodies in the cold, oxygen-poor depths of the ocean.
Why do octopus and squid have blue blood? Finally, why do octopuses have blue blood? Are you still wondering why octopus blood is blue and what the three hearts do? Well, the blue blood is because the protein, haemocyanin, which carries oxygen around the octopus’s body, contains copper rather than iron like we have in our own haemoglobin.