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In this Moment of Science Yael and Don discuss how women can see more color.
 
Yael: Not only are eight percent of men colorblind, but even compared to men who can distinguish between reds and greens, many women may live a more colorful existence. That's because about forty percent of women possess two types of so- called red cones¹, a key gene² involved in enabling one to see the color red.

Don: There aren't any men with two types of this gene?

Y: No. That's because it's located on the X chromosome³.

D: I have one of those.

Y: Yes, you do, but one only, whereas women have two, a distinction that makes for a discrepancy⁴ in how men and women see color. This gene has three times the number of variations of most other genes⁵. Possessing a variation on this gene can inhibit⁶ one's ability to distinguish red from green. But a variation of this gene coupled with a standard version of the gene theoretically may allow one to see more shades of reds and oranges than the average person.

D: And the only way to get such a combination of this gene is to get your hands on two X chromosomes⁷.

Y: Which you, my dear friend, Don, are without.

D: If these women are proven to be able to see a greater range of reds and oranges, is there any advantage or disadvantage to such an ability?

Y: That's yet to be determined⁸. But some scientists think that the ability to distinguish subtleties⁹ in reds and oranges may have meant life or death for our hunter-gatherer ancestors. They hypothesize that since women were the primary gatherers, they needed to be able to distinguish between ripe and unripened foods, as well as between edible¹⁰ berries and poisonous imposters.