Some Blacks I have seen kinda look more Caucasian to me, especially their hair, which seems to more straight. Also, their facial features are more Caucasian-like.
An example of cultural selection: During times of New World colonialization, when interbreeding between white European settlers and native populations took place (including interbreeding between newly-imported slaves and both the native populations and white settlers), lighter skin tones became the desired ideal.
In other words, a person's status in society went up as his skin tone became lighter (more white).