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Octopuses Have Three Hearts And Blue Blood
Unusual

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.

Source

https://en.wikipedia.org/wiki/Octopus

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Published
March 29, 2026
views
95
UnusualBiologyAnimalsOceanWeirdOctopusHeartsBlue BloodMarine BiologyCephalopod

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