In Octavia Butler’s Lilith’s Brood (aka Xenogenesis) which consists of the books Dawn, Imago, and Adulthood Rights, the few remaining traces of a post nuclear war humanity are saved by a race of aliens called Oankali. All Oankali technology is biological. Everything they need, they grow, to include their giant space ships. The Oankali keep the humans in suspended animation for hundreds of years while they set about fixing the Earth. They return it to a veritable Garden of Eden. No trace that humans had lived there remain. The Oankali plan to return the sleeping humans to the Earth to begin again. There is a price. The Oankali are natural genetic engineers. One of their three sexes, the ooloi, is the one who takes genetic material from the male and the female and creates a new life within its womb-like organ known as yashi. The humans who are awoken from hybernation and who are to return to the Earth are initially given two choices: 1) Live very long (3 - 4 times the normal human lifespan), healthy lives without any chance to have children again. You have already been sterilized while you were in hybernation. The Oankali will offer you no resistance if this is your choice, but neither will they help you. Remember, there is now zero human technology on the Earth. Zero. Or…. 2) Live very long (3 - 4 times the normal human lifespan), healthy lives in families that consist of a human male and female, an Oankali male and female, and an Oankali ooloi. Have as many children as you like, knowing that these children will always be the creation of four parents within the ooloi. Although there is still no human technology to speak of, Oankali bio-tech is very much at your disposal. Do you hold to human solidarity knowing that your generation is the last and only of its kind, or do you go with the Oankali knowing that humanity will continue, but only in a very different form? Remember, you as one of the humans the Oankali will return to the Earth are a survivor of the nuclear war and remember very well the Earth, just as it is right now, today.