EDIT: I want to emphasize that I really think that persistent racial injustices is a worthy topic, even though I just said it's a "valid point". Also, eevilspock is, I think, making a good point about the current injustices against blacks in America in a comment further down in the thread. He also distinguishing in that comment that it isn't whites as a race but that it is their culture and their place of power over blacks in history...and that in some alternate history, it's possible roles can be reversed. A first reading of his post seems like he is lumping all whites into a bin which is racism in my view, but after reading his second comment, I can see he might have not meant to come across in that way.
"there is nothing particularly "natural" about viewing people with darker skin and curlier hair as inferior. Drake surveys all perceptions of people with darker skin, curlier hair, or both across history. He finds very little consistency and concludes that racism, as we know it, is basically a product of the slave trade, which is to say the seizure of power." [1]
This isn't saying that racism didn't exist before the European enslavement of Africans. It's saying that the racism that exists today, and the concept of racism is linked to slavery, and is very different from racism that occurred in different eras, cultures, and regions of the world. You could say racism has been invented many times by different people, for different reasons.
[1] http://www.theatlantic.com/politics/archive/2014/06/the-case...
Surely it's changed more than a little. I think it's possible to say there's still work to do without having to claim that race relations remain essentially unchanged from the 1700's.
It is the inclination of the average (wo)man to take from all those who are at a disadvantage and offer little, if anything, in return. Race was just one metric used to justify and control this behavior, but it is not inherent to it.