How Blue Blood Helps Survival
The blue color of octopus blood comes from a copper-based molecule called hemocyanin, which is different from the iron-based hemoglobin in human blood. Hemocyanin works better than hemoglobin in cold and low-oxygen environments exactly the kind of places octopuses often live, like deep under the sea. This special adaptation helps them survive in extreme ocean conditions, making them one of the most intelligent and resilient invertebrates in the animal kingdom. Shutdown123