i have noticed this too, especially in commercials where a blacks are playing a black family unit. it is usually a darkskinned male with a mulatto wife and a mixed race/curly hair looking child. i have never seen where the roles are reversed e.g a mullatto husband with a dark skinned wife. i find this extremely odd to say the least in addtion when they need to cast a black token character in soaps it is always a someone who is clealy mixed race.