I don't recall the source, but I remember learning that dry earwax is almost unheard of in people of African and European descent. It's most common in Asian people.

Even more interesting is that there is apparently a very strong correlation between the type of earwax you have and whether or not your body odour (sweat-related) is strong. I was surprised to learn that many asian people never use deodorant because they simply don't need it.