Among other things, the Tarantinos stripped paint from faded black concrete floors and tracked down their original red pigment.

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This works because the red pigment is physiologically costly to produce.

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He said that not only did people with red hair have less protective pigment than people with darker hair, but the pigment they did have appeared to be more likely to react to produce harmful agents associated with cancer.

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These beads even bore traces of red ochre, used as a pigment.

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To prove it worked, he started with a strain of the E. coli bacterium that produced small quantities of lycopene, the pigment that makes tomatoes red.

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