I appreciate your efforts to spell things out. I have to say I'm getting confused, though

You started by making an argument that listed a series of stages (virus, bacterium, nematode, man) and claimed that at no stage along the way (before the last) were any kind of normative concepts applicable.

I meant to say that at no stage -including the last!- does the addition of merely naturalistic properties turn a thing into something subject to norms -something of which it is right to say it ought, for its own sake, to do this or that.

I also said that the sense of right and wrong and of purpose which biology provides is merely metaphorical. When you talk about "the illusion of teleology in nature", that's exactly what I was getting at (or so it seems to me). That is, teleology in nature is merely illusory, but the kind of teleology needed to make sense of rationality is not - it's real. Can you live with this? I think a lot of people are apt to think that illusory teleology sort of fades into the real thing with increasing physical complexity. I see the pull of this idea, but I think it's mistaken, and I hope I've at least suggested that adherents of the view have some burden to try to defend it.

Do you believe it is possible to tell a teenager what she "ought" to do?

Now that is a whole other can of worms...

At what stage in development do normative judgements become applicable.

This is a fair and a difficult question. Roughly, another individual becomes suitable for normative appraisal when and to the extent that s/he becomes a recognizably rational agent -ie, capable of thinking and acting for her/himself and contributing to society (again, very roughly). All kinds of interesting moral issues lurk here, but I don't think we have to jump to any conclusions about them.

In case I'm giving the wrong impression, I don't mean to be implying that people are bound by norms in virtue of possessing some special aura or other spookiness. I'm not giving a theory of the nature of norms - that's just too hard. All I'm saying for the moment is that if you stick to purely natural science, you won't find a place for them.