Okay I have a headache..

I am trying to figure out this dunn or sorrel thing.. I had colors.. just call em red,brown,black..and white.

Then everyone could sleep better. What is this counter shading thing everyone is talking about?

I don't know he is light and I just thought that was darker by the roots. I don't have any photos so can someone clearly advise on what the major differences are?

And do you know why they needed to be seperate?