I think that I'm going to like Mothership: Tales from Afrofuturism and Beyond if all the stories are of the caliber of the first: "I Left My Heart in Skaftafell" by Victor LaValle. Opening the collection with an urban fantasy myth was a good choice. I was expecting science fiction, robots and space stations, but was presently surprised with the gift of myth.
LaValle's story fits the race theme of the collection's introduction nicely. An African-American man vacationing in Iceland, taking a bus touring the coast and glaciers. He notices at once that he is being stalked by a troll (an honest to god troll). I'll leave the myth and troll for your reading pleasure and (in my whiteness) attempt to tackle the race theme in the story.
The narrator is black. The narrative is told from the first person perspective. Thus, the narrator freely describes the his interactions with other cultures and races, none of which are pleasant. The Northern Europeans, the Asians, and the Africans all want nothing to do with him. The Icelanders, however, find him to be most pleasant (for an American). Thus, he is alone, an outcast because of his race among tourist (also not of the Icelandic decent). Easy pickings for a hungry troll.
I don't know what the future will look like, what races will be left. Perhaps, we will all be one race, the gene pool completely mixed and perfectly blended. One thing will be for sure though; we will find a different reason to segregate and hate. To me this is sad, but one likely meaning that can be found within the myth.