Octopuses are fascinating creatures, and one of their most unique features is their three hearts. Two of these hearts pump blood to the gills, while the third pumps it to the rest of the body. Interestingly, the blood of an octopus is blue, due to the presence of hemocyanin, a copper-based molecule that helps transport oxygen. This is in contrast to human blood, which is red due to iron-based hemoglobin. Hemocyanin is more efficient in cold, low-oxygen environments, which is why it is well-suited for the octopus's ocean habitat.

Why Octopuses Have Three Hearts

The reason octopuses have three hearts relates to their unique circulatory system and their ability to survive in their deep-sea environment. The two hearts that pump blood to the gills help oxygenate the blood, while the third heart circulates the oxygenated blood throughout the rest of the body. When an octopus swims, the heart that pumps blood to the body actually stops beating, which is one reason why octopuses prefer crawling to swimming. This complex system helps the octopus maintain its highly energy-efficient lifestyle in the depths of the ocean, where oxygen levels can be low. Shutdown123