Octopuses Have Three Hearts and Blue Blood
These incredible marine creatures possess one of the most unique circulatory systems in the animal kingdom.
How It Works
Two hearts pump blood to the gills, while the third pumps blood to the rest of the body. Interestingly, the main heart stops beating when they swim, which is why octopuses prefer crawling.
The Blue Blood Mystery
Instead of iron-based hemoglobin, octopuses use copper-based hemocyanin to carry oxygen, giving their blood a blue color. This adaptation helps them survive in cold, low-oxygen environments.
Related Trivia
Camouflage Masters
Can change color and texture in 0.3 seconds
Tool Users
Use shells and rocks as portable shelters
Escape Artists
Can squeeze through any opening larger than their beak