Well, sometimes it is. But usually it's at least a slightly different colour. This comes down to uneven distribution (over the human body) of the melanin pigments that give hair colour.
There are two types of melanin. Eumalin is sometimes called brown/black melanin, and is pretty much those same colours. Phaemelanin (sometimes called red melanin) is much lighter. The ratio of Eumelanin to Phaemelanin determines your hair colour, from black to brown to red to blonde.
The thing about these ratios is that they can vary over the entire human body. This is partly why hair on the head often has lighter or darker streaks in it. Men can have beards that are different from their head hair colour. And the hair under arms or around the crotch tends to have more Eumelanin and less Phaemelanin compared to other parts of the body. Pubic hair also is curly regardless of whether your head-hair is, and it grows to a relatively short length before falling out.
There are two types of melanin. Eumalin is sometimes called brown/black melanin, and is pretty much those same colours. Phaemelanin (sometimes called red melanin) is much lighter. The ratio of Eumelanin to Phaemelanin determines your hair colour, from black to brown to red to blonde.
The thing about these ratios is that they can vary over the entire human body. This is partly why hair on the head often has lighter or darker streaks in it. Men can have beards that are different from their head hair colour. And the hair under arms or around the crotch tends to have more Eumelanin and less Phaemelanin compared to other parts of the body. Pubic hair also is curly regardless of whether your head-hair is, and it grows to a relatively short length before falling out.
