The argument seems to fail at: "I believe that neither morality nor values at the very core depend on minds being conscious or experiencing pleasure or suffering." The author evidently believes that, but fails to substantiate it. And anyway, Harris' criterion isn't about pleasure vs. suffering, but well being vs. suffering.
The idea that animals can have an ethic seems nonsensical to me. Only conscious, reflective, language-using beings can have an ethic or morality, because an ethic is by definition a self-consciously-held code of conduct, and a morality is by definition a self-consciously-shared code of conduct, which can obviously only be held, read, understood and shared by self-conscious language-users.
Criticisms of Harris usually boil down to, "But what about Hume's is/ought, eh, EH??!!" Oddly, this article seems to commit that very fallacy : obviously, just because genetically-mandated behaviour is, doesn't mean it ought to be. The error is as old as Social Darwinism, and it's surprising to find someone falling for it in this day and age.
In trying to refute The Moral Landscape: How Science Can Determine Human Values, in the way that the linked blog does, I believe that it’s quite unimportant whether or not
What the linked Darwinian response criticises Harris for, among other things, is that he doesn’t formulate a rightness criterion, despite that he claims that science implies some kind of impartial hedonism. But...
I noticed that there has been some earlier discussion about Sam Harris’s Moral Landscape Challenge here at LW. As a writer on the Swedish politico-philosophical blog The Inverted Fable of Reality, I would like to share a response to the challenge, written by our main contributor, which I believe is interesting to read even if you are not familiar with The Moral Landscape or its content. See this link for the response and a short explanation of the challenge.
The response takes a different approach to most responses to the challenge. It is divided into four parts and starts by asking which ethic is most compatible with science and reality and finally tries to answer this question.