I am totally baffled by your comment. Help me understand the distinction you are making between these two positions:

It’s clear that we don’t evolve every trait that would be useful

she is merely saying that monogamy will evolve when it is useful enough to increase the chance of survival.

I must be missing an important nuance, because I agree with your first sentence but strongly dispute the second one.

But I also agree with Jared* in #9: Ms. Judson doesn’t seem to be saying that monogamy is not useful because it hasn’t evolved; she is merely saying that monogamy will evolve when it is useful enough to increase the chance of survival.

Here is a real-life practical example of how something very useful may not evolve in the presence of a competing trait:

In Neil Shubin’s book Your Inner Fish, he explains how all mammals have essentially the same olfactory sensors, but in species with rich color vision (like humans), most of these sensors have mutated to the point where they are no longer useful for smelling. The presumption is that rich color vision has proven to be more useful for survival than highly functional smell. So natural selection keeps the sense of smell sharp in many species. But in species with rich color vision, smell is less important for survival, so mutations can more ealisy arise and compound over time. Dolphins (which are also mammals) have olfactory sensors that have mutuated completely beyond use, presumably because they are of no use in the water, so there is no force of natural selection keeping that trait sharp.

Thanks for the comment about Gould. Acknowledging the significant role of chance is important I think.

On the quote: You are correct about what she is saying, but she goes far beyond the non-controversial point you summarize. She says:

Judging by the low frequency of monogamy in nature, this is rarely the case.

From the low frequency of monogamy in nature, she concludes that it is rarely the case that stable couples are more successful at rearing offspring. You simply cannot get from the evidence to her conclusion without the assumption that when it is useful it will evolve.

I see this argument applying directly to your question about why monotony has arisen in some circumstances and not others.

Freudian slip?

On the other hand, I don’t find the quote as offensive as you. I don’t read her to be saying that if monogamy is useful it will evolve. Rather, when it does (rarely) evolve it is because it is more useful (metaphorically speaking, of course) than the norm. That seems like a reasonable presumption to me.

So one might legitimately wonder why a trait such as a monogamous instinct has evolved in some circumstances, while it is pointless to wonder why firebreathing has never evolved anywhere.

I don’t know, I can replace firebreathing with plenty of alternates that do occur in nature but make the point equally well. Why haven’t humans evolved tough skin to protect against injury, or wings for flying, or better night vision? Is it because these are not useful for promoting survival/reproduction or is it simply because evolution relies on random mutation and you don’t always get what might be useful.

I see this argument applying directly to your question about why monotony as arisen in some circumstances and not others. One really obvious possibility is that the random mutation generator created it in one circumstance and not the other one we are comparing to. If that is the case, we learn nothing, and I don’t see how this can be ruled out.

On your last paragraph beginning “the real logical flaw” I totally agree. Very good analysis.

I think the idea is that it evolves genetically. Here is a quote from the article:

A full understanding of the genetics of attachment is still some way off. But one of the genes that has already been implicated is the arginine vasopressin receptor 1a gene.

Your question is a very important one since the nature/nurture debate comes front and center every time someone simply assumes that everything can be explained genetically. I think it is worth noting that natural selection can select for memetic behaviors as easily as it does genetic ones.

For current evolution there are some arguments that human evolution is actually accelerating. The evidence isn’t all in, from what I can see. But I think it undeniable that things like medical care and intermixing of groups once largely separated is giving evolution the ability to deal with new situations as well as changing the kinds of influence natural selection has to work with.

I suspect once sequencing individual genomes becomes cheap enough to be commonplace that we’ll gain a much better appreciation for how evolution is acting on humans the last few thousand years and today.