I'll get back to that in a second. I really would like an answer to this, though:
If that's the case, what are our most commonly accepted ethics but traditional habits?
I'm not sure that instincts enter into a discussion about morality and/or ethics.
I'm more of the view that morality and ethics are what happens when one rises above instinsts.
Gwalla distinguished between habit and instinct. Now, if you're putting forth that habit and instinct can be the same thing (or close enough to be indistinguishable), then my question still applies. If something is ethical, yet becomes habit and you stop thinking about it consciously, is it still an ethic? Or is it merely habit?
What the man is asking, and I'd like to knwo, too, is how do you draw a line between them?
The short answer to your question would be that instinct would be those things you do naturally without having learned the behavior, while habit is a behavior you do naturally because you've learned it through repetition. Generally the latter would need to first be prompted by some experience. However, with most things, the line would blur.
Example: If you have always avoided stealing without being prompted to do so, that'd almost certainly be instinct. If you have always avoided stealing because you were punished the first time you stole, that'd be habit.