After the brief discussion about genetics in class on Monday, I figured I'd talk about my understanding of the genetics involved and how they would affect Oankali form and society. Although our current understanding of genetics limits our engineering methods to basically linking one gene to a single protein or trait, it's become pretty clear in the last decade that our genome is much more complicated than that--we are exponentially more complex than a fruit fly, for example, but we have less than double the actual number of genes that a fruit fly has. Clearly, although the physical complexity must be genetically derived, it cannot be purely explained by our current understanding of genomics. Given that, I think it's fair to allow Butler some wiggle room on the capacity of the Oankali to engineer particular personality traits--things like aggression, caution, violence, sexual drive, etc.
We seek to assign moral or societal values to the behavior of the Oankali. In particular, their drive to "trade" with species after species seems appalling to us; they seem to genetically pillage other species, imposing their own biological and societal forms. However, attempts for us to place a moral judgement upon that behavior are essentially inappropriate. This drive is a subtle, genetic one; just as we have a basic drive to reproduce on a genetic level, the Oankali enact this sort of genetic colonialism because of a desire, a need that is fundamental to them. To judge them for it is the same as judging humanity for seeking sex.
The differences between humanity and the Oankali are even more extreme than first appears. Although they appear largely human when amongst us, it must be remembered that their original form was closer to a sea urchin or jellyfish than an ape. Societal forms and moral strictures forming in such a different species would be truly unknown and potentially unknowable to us; the Oankali are truly and completely foreign, from a genetic level up to the extrapolated society, and we must keep that in mind when considering their motives.