Paul,

That's a very good question, I'll do my best to give you an answer.

[Puts on Devil's Advocate hat]

Semi-rhetorical question: if one person says 'I saved the child because my genes directed me', and another says 'I saved the child because my morals directed me,' who is giving the more accurate account of their motive?

Sitting down to mull the decision over in a smoking jacket lets the child drown - this is as much reaction as decision. Hence, I think the first person's probably closer to the mark. You do have a moral duty to save the child, but your ethics-centre probably doesn't even get a word in before you're in the water. Why can you not call the part of the mind that takes that decision in a split second your 'genetic ethics'?

Caveat: genetic ethics, such as they are (or aren't), aren't rational, they are often the source of bias. But since when is morality rational? As long as we're talking about split-second judgment calls, our genes usually do pretty well by us.