These ten animals have blue blood, not red! Why is this? Do you know the reason?

When you think of blood, the first thing that comes to mind is its red color. Red blood cells contain a pigment called hemoglobin, which is responsible for the red color of our blood. It is very common for blood to be red. But did you know that blue blood also exists? Should you be surprised to hear this? Yes, most animal blood is blue.

While most vertebrates, including humans, have red blood cells due to hemoglobin, some animals have blue blood cells due to the copper-based protein hemocyanin.

This unique adaptation allows these creatures to thrive and live in specific environments, such as the deep sea or low-oxygen habitats.

What causes blood to be blue?

As mentioned above, hemocyanin uses copper ions to bind oxygen, giving the blood a blue color when oxygenated.

Unlike hemocyanin, which uses iron, hemocyanin is more effective in cold or low-oxygen conditions, which is ideal for these animals.

10 Animals With Blue Blood:

Horse Crab: Known for its biomedical importance, the blue blood of horse crabs contains hemocyanin. Their blood plays an important role in detecting bacterial toxins and is used in medical safety testing.

Octopuses: Octopuses are among the most intelligent creatures in the ocean. With three hearts and nine brains, octopuses also have blue blood, which helps them survive in the cold depths of the ocean.

Squids: Like octopuses, squids also have three hearts and a complex circulatory system with hemocyanin-rich blood.

Spider: The blood of the spider, which usually weaves webs in houses, is also blue. This system is especially useful for spiders that live in low-oxygen environments, such as underground burrows.

Lobsters: Their blood turns blue after oxygenation and flows through a single-chambered heart. Their blood helps them absorb oxygen in low-temperature, low-oxygen conditions.

Mollusks: They have an open circulatory system and use hemocyanin to transport oxygen. This helps them obtain oxygen while at the bottom of the sea.

Scallops: Like mollusks, scallops have open circulatory systems and blue-green blood.

Cuttlefish: Closely related to squids and octopuses, cuttlefish rely on hemocyanin to transport oxygen in their three-heart system, which gives their blood its blue color.

Amazon Milk Frogs: The blood of these frogs is blue, which makes them different from other frogs.

Brachiopods: These marine animals use hemerythrin instead of hemocyanin, resulting in a pale yellow blood. However, occasionally the blood appears blue.