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Blue BloodTopic

Blue Blood

1 fact

Uncover the intriguing history of 'blue blood,' from its origins describing royal and noble lineage to its surprising biological meaning in the animal kingdom.

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    Octopuses Have Three Hearts And Blue Blood

    Two hearts pump blood through the gills, while the third circulates it to the rest of the body. Their copper-based blood, hemocyanin, is more efficient at transporting oxygen in cold, low-oxygen environments, giving it a distinctive blue hue.