I know it is caused either by blood vessels beneath skin , or some pigment called "pheomelanin" . But what is it in fact?
closed as unclear what you're asking by Tyto alba, another 'Homo sapien', David, kmm, The Last Word Apr 17 '17 at 0:00
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The answer lies in hemoglobin, which is responsible for the transportation of oxygen throughout our bodies. It is the protein found in red blood cells, and thus it has a reddish hue to it. When an organism has lightly pigmented skin, the oxygenated hemoglobin causes the pinkish hue that you are describing.