The focus is on the difference and otherness of the aliens: physically different and ideologically different. On the one hand the oankali are technologically superior and the primary thing they do is engage in this genetic trade. Their drive to engage in the trade of genetic material is key to their belief. Its key to how they don"t become stagnant as a race. Its about an understanding of the change in evolution. Lilith is our access to and our means to interpreting the oankali and how different and other they are from humanity. Its her experience of difference and otherness that guides our understanding of the text. Lilith"s understanding of the physical appearance starts out as something that seems to be different and then there is a definite understanding that he is radically other: this tension remains through out the entire text.