Naturalism's Ethics are Derived from Teleological Explanations?

Lawrence Solum has written a post in defense of naturalism-based ethics. Solum's tack is to first assure moral naturalists that their religion is being zealously defended from attacks by traditional philosophy, and second to summarize the apologists' arguments. Given the nature of the defenses, however, I'm very doubtful that naturalists accept these purported defenses because they rely on premises specifically rejected by naturalism (as I know it).

I concede that my familiarity with the subject stems solely from books, and I admit to having read only one book in defense of the emotive theory of logical positivism, the response Sollum offers to the is/ought gap. The arguments Sollum represents as the strongest available were made in this book, The Logic of Moral Discourse, by Paul Edwards, so I have no reason to believe I am attacking weak forms of the argument. However, if someone can refer me to an essay, or short book (exposing the error of the is/ought gap or the naturalistic fallacy shouldn't require more than 1000 words) I would gladly read it. I mention this because I wasted 240 pages of print and 5 hours of my life chasing Edwards claim that he was going to bridge the is/ought gap, but he never did. Life is too short to spend time reading books that can't fulfill their claims, so no foolish claims, please.

Solum uses the teleological argument, the idea that one can deduce nature's purpose through observation, as the basis for his attack on the is/ought gap. The excerpt from Elizabeth Anscombe specifically endorses the "teleological explanation." But as anyone familiar with the debate surrounding Intelligent Design (the argument for God's existence based a teleological explanation of nature) knows, naturalists reject the argument precisely because it rests on a teleological explanation. This is why I was so surprised by the content of Solum's defense. And while it's possible that their is a subset of naturalists that accept teleological arguments, they are completely absent from the Intelligent Design debate.

All naturalists that I'm aware of specifically deny that nature has any purpose. When someone claims to see purpose in nature, naturalists argue, they are actually just projecting their preconceived ideals. Take something as seemingly purposeful as the sex-drive. If you asked most people for the natural purpose of the sex-drive, they would sensibly tell you that its purpose is to motivate animals to copulate so they'll reproduce. Not so, answer the naturalists. The sex-drive has no purpose. It's just that those animals that have a sex-drive are likely to reproduce. Those with no sex-drive are unlikely to reproduce. Nature didn't try to make animals with sex drives -- nature didn't have a purpose -- animals with sex-drives just happened and they survived.

Solum's hypothetical of the xenobiologist similarly offends naturalism because it depends upon the reader's ability to project values. But the naturalistic fallacy challenges the reader, and the xenobiologist, to question whether their values, the values being projected on the subject, are, indeed, good values. Nature cannot even tell the biologist that "flourishing" is good and "dying" is bad.

UPDATE: Searching the web for information, I discovered that emotive logical positivism, or descriptivism, is frequently called "naturalism." I suspect Sollum confused these distinct theories with the same name that don't have anything to do with one another. That's why he offered the emotive theory of logical positivism as a defense of Dawkin's ethics. Naturalism (emotive logical positivism) is based on teleological arguments. Dawkin's naturalism (antagonist of Intelligent Design) rejects teleological arguments.