What is the theme in Lilith's Brood by Octavia E. Butler?

Another theme in the book is the sanctity of life. The sanctity of life is the drive for the Oankali rescuing the Humans. There are quite a few chapters that focus on the reason that these creatures were so willing to come in and pick up the survivors from Earth. They found in the Human race a great contradiction and blame this contradiction for the reason that Humans were almost successful in destroying themselves.