Just an observation.
If you look at the typical appearances of the people of the world, Caucasians tend to have the most variety.
Hispanics/Africans/African Americans all tend to be darker with dark hair and brown eyes.
Asians all tend to have the olive skin tone with the black hair and black/brown eyes
And then there are the white/Caucasians who are vastly different. They can have blond hair, black hair, brown hair, red hair, green eyes, blue eyes, brown eyes, grey eyes...
So why is that? Is there a pigment or something that causes the variation?
Most Helpful Guy
Essentially, the pigment which causes brown skin and brown eyes is just darker than other pigments, so regardless of whatever other pigments are present, brown is the one that's going to be visible.
However, there's as much variation within other races, but they vary in different ways - for example, people from one race might all have generally similar eyes but different noses, while people from another race might all have different eyes but generally similar noses.
The way the brain recognizes faces is highly specialized (we're much, much better at recognizing other people than we are at recognizing individual sheep, for example), and works by focusing on the parts that are most variable.
If you don't grow up around Asian people, you might find "all Asians look alike", because your brain doesn't know what to look for. If you do grow up around Asian people, you're less likely to have that problem, even if you are not Asian yourself.0