I hope I wasn't alone in feeling a burrowing sense of discomfort as I read Ruse and Wilson's piece (thanks for the Kitcher piece Slater; that helped calm me down afterwards). I gathered their conclusion to be that morality is essentially derived from the product of our evolutionary history, our genes. Although they acknowledge that genetic interactions (and epigenetic influences) are more complex than we currently understand, they also seem to be comfortable with believing that as science marches on in human genetics, we will eventually be able to explain our personality traits, social structures, moral codes, political leanings etc. through our genomes.
This is a very reductionist and deterministic approach to genetics and our human dignity. We're assuming that everything about us as humans can be explained by genetic characters, and that if we possess certain genes we'll surely develop some particular trait or disposition. Ruse and Wilson seem to be taking the "nature" side only of the "nature vs. nurture" debate.
But what if it's not so simple (or complex, depending on how you ask the question)? Isn't it entirely possible that something outside of genetics has come to influence how we reason and brought us to where we are today? In pondering this question, the philosopher/cognitive scientist Daniel Dennett (Tufts University) came to mind (he gave a talk entitled "From Animal to Person" at WSU's Potter & Holland Lecture in September). One of his theories about the development of modern human consciousness and reason is that "memes" (a term coined by Richard Dawkins) have guided evolution of culture in a way analogous to how genes and viruses have guided our genetic evolution. Memes consist of things like cultural norms, language, even those catchy jingles that get stuck in your head, which influence the way we think and act. However, unlike materialistic genes and viral mutations, memes are passed on through their persistence in social structures and ideas. Thus, memes can be thought of as the "nurture" side of the debate.
For all we know memes and genes could be the same thing, but I'm more inclined to think they're not. I'd be willing to consider that they influence each other to a certain extent, but not that to which Wilson and Ruse are willing to concede. I think this is a very delicate issue with far-reaching consequences if we accept the notion that genes endow us with our moral reasoning capabilities.
Another point on this, which Kitcher addresses, is that Wilson and Ruse trap themselves in a very relativistic approach to morality. They argue that since different species have evolved down their own paths, they have different systems of exercising moral reasoning (if any at all). Aside from the fact that all members of the species Homo sapiens does not share the same moral system (which they acknowledge, but that's beside my point), my primary disgruntlement with this claim is that "species" have not evolved independently of one another. Our evolutionary histories are inextricably connected, at least to the extent that all of the organisms here today are here together and have been since some point in time. This would seem to diminish the idea that we have completely different systems of reasoning just because we have different genomes.
Maybe I'm beating a dead horse here; sociobiology/social Darwinism aren't taken all that seriously anymore in mainstream philosophy/science. I just think we need to carefully analyze what's being proposed here, because these arguments carry huge risks to the world at large.
There's plenty of room for expansion on this topic.