The history of human cruelty is revolting enough, but the history of human justification thereof is infinitely more revolting.
Would it be any different in an alternate world, where Homo erectus still existed alongside of us Would we treat our evolutionary cousins any better than we've ever treated our own kind? Harry Turtledove takes a hard look at this question in A Different Flesh, and comes up with some answers we'd probably just as soon not hear.
Preface
WHERE DO:YOU get your ideas?
I've never known a science fiction writer who hasn't been asked that question a good many times. I'm no exception. And, as is true of most of my col eagues, the answers I give often leave guestioners unsatisfied. I've had ideas doing the dishes, taking a shower, driving the freeway. I don't know why they show up at times like those. They just seem to.
Sometimes ideas come because two things that by rights ought to be wildly separate somehow merge in a writer's mind. I had just finished watching the 1984 Winter Olympics when I happened to look at a Voyager picture of Saturn's moon Mimas, the one with the enormous crater that has a huge oentral peak. I wondered what skijumping down that enormous mountain, under that tiny gravity, would be like. A story followed shortly.
And sometimes ideas come because you look for them. Like most science-fiction writers, I read a lot. In late 1984, I was idly wondering how we would treat our primitive ancestor Australopithecus if he were alive today.
What I think of as my story-detector light went on. How would we treat our poor, not-quite-so-bright relations if we met them today. I soon dismissed the very primitive Australopithecus. As far as anyone knows, he lived only in Africa. But Homo crectus, modern man's immediate ancestor, was widespread in the Old World. What if, I thought, bands of Homo erectus had crossed the Siberian land bridges to America, and what if no modern humans made the same trip later? That what-if was the origin of the book you hold in your hands.