Two hearts pump blood to the gills, while the third pumps it to the rest of the body. When an octopus swims, the heart that delivers blood to the body stops beating, which is why they prefer crawling over swimming. Their blood is blue because it uses hemocyanin (copper-based) instead of hemoglobin (iron-based) to transport oxygen.
Two hearts pump blood to the gills, while the third pumps it to the rest of the body. When an octopus swims, the heart that delivers blood to the body stops beating, which is why they prefer crawling over swimming. Their blood is blue because it uses hemocyanin (copper-based) instead of hemoglobin (iron-based) to transport oxygen.