From a scientific point of view, the three-heart system in octopuses is an elegant solution to the challenges of their environment. Their copper-based blood protein requires extra help to move oxygen efficiently. Having two hearts dedicated to sending blood to the gills ensures oxygen pickup is fast, while the main heart pumps oxygen-rich blood to the body to power their complex movements and intelligence. The fact that the systemic heart stops during swimming shows how evolution shaped their behavior and physiology for energy conservation.