Why is the skin around my genitals darker than the rest of my body?

Question

I've noticed that the skin around my genitals are a lot darker; think a darker shade of peach against the rest of my body. Of course, I'm well aware the skin around your nipples seems to be just the same color as the skin around my genitals, but I'd like to understand, why is it this way?

Why is the skin around my genitals so much darker than the rest of my body? I'm fairly sure I don't sunbathe naked, and most of the time my privates are being protected by a few layer of clothing, so what could make the pigmentation so much darker than the rest of my body?

Answer 1

Inesophet actually had a good answer there, and I'll expand on that.

Pheomelanins impart a pink to red hue, depending upon the concentration. They are particularly concentrated in the lips, nipples, glans of the penis, and vagina.

Meanwhile, there are two types of eumelanin: brown eumelanin and black eumelanin—which chemically differ from each other in their pattern of polymeric bonds. A small amount of black eumelanin in the absence of other pigments causes grey hair. A small amount of brown eumelanin in the absence of other pigments causes yellow (blond) color hair.

Optional Reading: http://www.fasebj.org/content/5/14/2902.full.pdf

Sources:

http://www.metacyc.org/META/NEW-IMAGE?type=COMPOUND&object=CPD-12380 http://www.metacyc.org/META/NEW-IMAGE?type=COMPOUND&object=CPD-12379

Answer 2

Different kinds of Melanin. the one on the Lips Genitals and nippels is Pheomelanin. While the one in hair and skin is Eumelanin.