A closer look
Octopuses possess three distinct hearts and blue, copper-based blood to survive in deep, freezing ocean waters. Two of these hearts pump blood to the gills, while the third circulates it to the rest of the body. Interestingly, when an octopus swims, the heart that delivers blood to the organs actually stops beating, which explains why these creatures prefer to crawl rather than swim, as swimming exhausts them quickly. So next time you feel tired after a light jog, just remember that at least your cardiovascular system doesn't shut down mid-stride. Evolution really looked at these squishy sea aliens and decided to give them a biological handicap just to keep things fair. It is deeply comforting to know that even one of the ocean's most intelligent predators is fundamentally too exhausted to deal with basic physical exertion
