Their blue blood contains hemocyanin, which turns blue when it binds with oxygen. Their blood can appear purple due to the presence of a pigment called hemerythrin, which is purple when oxygenated.

The world is filled with a spectrum of colours. From firing red to soothing blue, you can find a range of hues. However, here's a small fun fact for you. You may have seen a myriad of colourful ...