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How Blood Evolved (Many Times)

submitted by Aard Vark

(oritteropo)
5 years 3 months 1 week ago

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YouTube description:

Blood is one of the most revolutionary features in our evolutionary history. Over hundreds of millions of years, the way in which blood does its job has changed over and over again. As a result, we animals have our familiar red blood. But also blue blood. And purple, and green, and even white.