As the trilogy’s first book, Dawn, opens, the human race has nearly destroyed itself by nuclear war--"humanicide," as Butler calls it--a fate that seemed all too plausible in the eighties, when the book was written, and that remains a distinct possibility if the effects of humanity on our environment are not reversed. The few humans who survive the war are rescued and captured by the Oankali, a nomadic alien species that travels through the universe seeking partner species with whom to "trade" their own genes. The story is told from the viewpoint of Lilith Iyapo, a human woman whom the Oankali adopt into their family and try to enlist in recruiting other humans. Lilith is torn between accepting the medical enhancements and the sexual advances of her captors while trying to help other humans escape.
Unlike the vast majority of alien abduction tales, Dawn actually presents a biologically plausible explanation for why the Oankali need to interbreed with humans--despite their own abhorrence for the human race, which to them appears monstrous for its combination of high intelligence and self-destructive violence, the "human contradiction." The Oankali have evolved specialized organs and subcellular structures which manipulate their own genes to maximize fitness in their environment, a self-sustaining starship which is itself a living organism. Paradoxically, because the Oankali are such successful genetic engineers, they tend to engineer themselves into an evolutionary dead end; losing all genetic diversity, they lose the ability to adapt to change. The only way they can recover genetic diversity is to interbreed with an entirely new species, which contributes new genetic strengths--and weaknesses.
