katja z wrote:Xenophobia has probably existed since forever, but the particular idea of classifying people according to their looks (particularly skin colour) and assigning different values to these categories is a relatively new one.
Homer talks about races in terms of appearance. I don't think visually based racism is as recent as you may think.
Racism can also be subtler and more pervasive than people realize. For example, based on the pictures early in this thread, people seem to be making the assumption that "mixed race" means a black/white mix. In fact, there are other mixes of races that don't include black, or don't include white, or even include neither (east asian/polynesian or east asian/australian aborigine), so that assumption is actually a racist one, even if it's unintentional.
Finally, I want to note that the genetic data is not nearly as clear cut as some people on this thread seem to think. The "recent out of Africa" hypothesis was popularized based on mitochondrial and Y chromosome data. Unfortunately, mitochondrial and Y chromosome lineages only branch and don't merge - unlike the other 97% of the human genome - so they can't reflect any mixing within larger populations. For example, if the multiregional hypothesis is correct, it couldn't be reflected in mitochondrial and Y chromosome data, because it would require the tracking of contributions from both parents, not just one parent at a time. As a result, that data has provided a rather distorted view of human lineages.
More recent autosomal data has essentially disproven the recent out of Africa hypothesis in its strictest form. East Asian autosomal genes contain some content - on the order of 20% - with a coalescence date not in the 100,000 years ago range required by the recent out of Africa hypothesis, but rather in the 2,000,000 year range corresponding to the homo erectus radiation. That would still be "out of Africa", but much longer ago. And of course if you go back far enough - around 10 million years ago - apes originally developed in south Asia and only then migrated to Africa, so we're all "out of Asia" too.
This is still an area of science where we know very little, and the confidence in any clear cut hypothesis is low. For example, there was a mitochondrial DNA discovery from Siberia very recently that's also rather difficult to square with "recent out of Africa". People who are interested should keep their minds open on the hypotheses and theory, and keep up to date with the new discoveries.