Like Zaki, Michaels takes the Xenogenesis trilogy
as an opportunity to comment on 'the essentialist/ antiessentialist debate', but, unlike Zaki and other participants in that debate, he sees the two positions as more similar than different, because they both have an investment in 'maintaining difference'; whether the status of that difference is physiological or cultural, essential or constructed, is of secondary importance.
Butler's personal view seems to be that our "hierarchical" tendencies, as described in the Xenogenesis trilogy, have an inescapably violent effect on our interactions: though the human resisters who refuse to mate with the Oankali are finally allowed to settle by themselves on Mars, there is no suggestion that anything in their fundamental nature has changed to prevent them from destroying themselves with nuclear war just as before; similarly, the most arbitrary cruelty in Clay's Ark and Fledgling is inflicted not by the communities of blood-sucking or diseased hybrids but by the fully-human gangs that capture and torture others by choice and out of their own aggression.
Contemplating and Contesting Violence in Dystopia: Violence in Octavia Butler's Xenogenesis Trilogy.
The High Cost of Cyborg Survival: Octavia Butler's Xenogenesis Trilogy.
Embracing Otherness': An Examination of Octavia Butler's Xenogenesis Trilogy.
The Human Contradiction': Identity and/as Essence in Octavia Butler's Xenogenesis Trilogy.
Although Doro's violent feeding on the minds and bodies of normal humans springs to mind as an example of a cannibal trope in Butler's work, the figure is more subtly apparent in the dynamic between human and Oankali in the Xenogenesis trilogy, in which the last humans resist their alien saviors precisely because the conditions of salvation include wholesale incorporation of body, mind, and society.
In the Xenogenesis trilogy, the Oankali who save the remnants of humanity are through genetic engineering able to extend human lifetimes into the hundreds of years, but at the cost of their individuality; in the Patternist series, roles often filled by external technologies (weapons, transportation, communication) are filled by abilities which inhere in the biological makeup of mutated humans; in the Earthseed series, technologies of bodily destruction, control, or expression play significant roles in the narrative (weapons; electronic collars; immersive "masks" for virtual reality).