xenogenesis Author:octavia e. butler We had done our best to destroy ourselves, but in the aftermath of Earth's final war, the Oankali arrived. They rescued as may people as they could, then set about to make the devastated planet habitable again. The price of their aid: the irreversible transformation of humanity into something else. For the Oankali were genetic engineers -- a ... more »race that had survived by interbreeding with other species...gene traders who, by constantly evolving, avoided the specialization that meant extinction or stagnation for other beings.« less