Here's an interesting individual observation: the author of the Bitch, PhD weblog is in an open marriage. Personally, I couldn't do that—I at least need the illusion that I'm someone special—but if someone other than my wife finds a different kind of relationship that works well for them, more power to 'em, and I'm certainly not going to impose my personal preferences on them. Strangely, though, some people find other people's relationship choices offensive.

I normally wouldn't care…there are always narrow-minded moralizers who will whine about what other people do with their own genitals, but in this case, the complainer tries to argue that there is a biological justification for castigating women who don't do as he thinks they should. The naturalistic fallacy is called a fallacy for good reason, but even without that, he makes a series of claims that are just plain bad logic, in addition to being poor biology.

1. Open relationships are likely to cause sexual jealousy, as even supporters acknowledge.

Closed relationships are also fraught, in many cases, with sexual jealousy. So what? The quote he cites doesn't even make the claim he says it does: it says, "Open relationships challenge us to confront our jealousy and possessiveness", which does not mean that they cause jealousy, but that we are often jealous, and people have to work against that feeling in an open relationship. You also have to work against it in an exclusively monogamous relationship.

2. Sexual jealousy is universally acknowledged as a powerful force in our relationships, even by those who deny that human biology affects human behavior.

First of all, I can't stand people who claim that others deny that biology affects behavior—it's as annoying as if I were to claim that this guy denies that culture has anything to do with behavior. It's patently false, so let's stop erecting strawmen.

The rest of this point consists of a quote showing that a lot of violent behavior is motivated by jealousy. Yeah, OK, I can see how jealousy would drive some vicious behavior. But the point is...? If you're arguing that sexual jealousy is a bad, bad thing, I could see going into examples of ugly jealous behavior, but this author wants to argue that it is an inevitable force and we must surrender to it. It's rather like reading about all the wars and hatred and violence fomented by dueling religions, and finding that the author's conclusion is that we must now all pick a god of our own and defend it to the death.

3. The consensus view among evolutionary biologists is that sexual jealousy is hardwired because it increased reproductive fitness, in both other animals and humans, including MIT's Stephen Pinker:

Aargh, another great annoyance: there is no such consensus view. What he cites is a view held by evolutionary psychologists, which is by no means the consensus among biologists. I certainly don't accept it. There is absolutely no evidence that such a specific behavior is in any way 'hardwired' in humans. It is much simpler to propose that we have a hardwired but general reward system that couples certain phenomena to pleasure; sex, among many other things, triggers that reward system; and we tend to struggle via a great many strategies to maximize rewards. Different strategies will work to maximize access to sex under different conditions; you don't get to argue from the existence of a general desire to the idea that only one particular strategy is a universal and inviolable optimum.

The article he cites to back up this claim is a book review by Mark Ridley of one of Pinker's books:

He discusses how natural selection will theoretically favor sexual jealousy, and how the facts (Margaret Mead and disciples notwithstanding) match the theory. Sexual jealousy, I agree, is a Darwinian adaptation that enabled some ancestral humans to outreproduce their more relaxed contemporaries, who did not end up among our ancestors.

Note: no evidence for a hardwired 'sexual jealousy' component is given, a common problem when dealing with evolutionary psychologists. The existence of an argument is apparently sufficient evidence for the existence of a phenomenon.

I will now mention a word that makes many evolutionary psychologists cringe in disgust: spandrel. Sexual jealousy is nothing but a side effect of that general reward system I mentioned above. It's a more parsimonious explanation than inventing fixed neural circuitry for which there is no evidence, and is more accommodating of the observations of the diversity of human relationships.

4. A large % of divorces are caused by adultery. Here's one of the first hits I found for the UK. 29% of divorces in the UK were caused by adultery in 1989. I can find more sources if anyone seriously disputes this.

So, in other words, closed, exclusive relationships, such as are typically found in most Western marriages, have a significant frequency of failure. This is an argument against open marriage...how?

5. Divorce causes a huge drop in the standard of living of the wife: drop in standard of living of females after divorce as of 2000: 45%

6. single mothers tend to be net tax recipients and live in poverty:

Are all these divorcees and single mothers proponents of open marriage? I suspect not. It seems to me that these facts clearly show a huge economic disincentive in our culture for people who want to follow different relationship strategies, or want to break off bad relationships altogether. How is the fact that women are often treated as chattel, lashed with the whip of poverty, evidence that they are driven by internal biological imperatives to behave in a certain way? I would be more impressed with the evidence if women and men were on an entirely equal footing, with no social and economic pressures compelling them to act a certain way, and they then spontaneously formed stable monogamous relationships.

I think what this fellow has done is demonstrated that there is no reason to suspect biology is directly involved in the cultural institutions around marriage, and that we ought to think more about social factors.

But the hard facts are above: sexual jealousy predictably does lead to the breakup of marriages, and single mother households do predictably lead to dependence on the state. So the facts are aligned against Mrs. B....and it's all downhill from here.

Against Mrs B? what facts? What's the argument? Is he seriously trying to support this assertion?

In all likelihood this woman's personal "reinvention" of marriage is sending her on a collision course towards a train wreck.

An awful lot of marriages are train wrecks when they follow the conventional rules. Relationships have to work themselves out in their own individual ways, and maybe one problem is that busybodies think they all must follow One True Formula, and seek to put constraints on the way other people live. Mr and Mrs B are trying to follow their own strategy for coexistence, presumably worked out in negotiations between themselves, the two people most intimately familiar with their own needs. It is not helpful for others who are unaware of their specific situation to dictate how they must live together.

I also find it peculiar that this person claims to be a libertarian. I'm no fan of the libertarian religion, but I had thought that at least one point in its favor was that it encouraged individualism and private liberty…is that not true?

There is another argument that he's trying to make:

Many of the simple rules that humans have lived by for generations have an evolved context to them. That is, they are culturally inherited traits that have probably increased the reproductive fitness of their carriers. Over time, there has been a gene-culture feedback loop to chemically hard-code some of these feelings (like sexual jealousy) into our behavior.

I'm a biologist. I say, show me the data. These are all blanket assumptions from the evolutionary psychology crowd, and are unsupported by anything other than their happy belief that Darwinian selection explains all, and that everything in human behavior is the result of adaptive selection.

Clearly that is not a particularly 1950's view of sex or sex roles, but Mrs. Phd's out of context quote makes it into a caricature. In fact, I'm wondering if she herself is a caricature of a self-destructively leftist humanities professor - can she really believe that stale, discredited Betty Friedan stuff in 2004? As one of my colleagues in biochemistry likes to say: can anyone really believe that feminist studies has anything relevant to tell us about "the social construction" of male-female interaction when degree recipients aren't even required to know the difference between the chemical structure of estrogen vs. that of testosterone, let alone anything about the comparative genomics of the X and Y chromosomes?

Oh, jebus.

I know quite a bit about estrogen and testosterone, their developmental and physiological effects, site of synthesis, etc., etc., etc. I know about the structure of X and Y chromosomes. I teach classes in which we discuss this stuff in some detail.

What kind of geek would think that knowing that estrogen's C19 is unmethylated while its A ring is aromatic gives him any insight at all into the different behaviors of the sexes? That is truly one of the saddest and most pathetic quotes I've run across in quite some time.