However, I was disappointed that you chose not to address my main point, which wasn’t about Bonobos or how they treat other animals within and outside of the troop. The issue is the difference between our brains and theirs…and why those differences might matter more than we like to admit. (Incidentally, I acknowledged that Bonobos are less violent with each other via a link to an article.)

Just to clarify, I’m certainly not saying that humans aren’t affected by the Coolidge effect. A lot of us fool around a lot. In fact, I think of our mammalian tendency to add mates when opportunity presents itself as our “mating” program. (I might also add that I don’t think of “promiscuous” as a loaded, moral term. It’s just the word I use for species that don’t pair bond.)

However, we humans also have a “pair bonding” program, which bonobos do not. Most humans are socially monogamous, and some miraculously do pair bond for life. These phenomena are simply not found in bonobos. Personally, I think we are naïve to insist that the only difference between us and them is our cultural and social wishful thinking (a point of view I often hear, but which you may not share).

I think evolution has left us with a painful tension between our tendency to form pair bonds and our good ole, ever-present mammalian add-a-mate program. Humans are sexually active beyond estrus, which encourages us to exhaust our sexual desire for each other (Coolidge Effect). Yet, at the same time, our limbic systems are set up to encourage, and benefit from, pair bonding—perhaps due to the exaptation of our underlying infant-caregiving attachment program, which makes us find affectionate, close, trusted companionship with a mate especially soothing.

I think it’s quite reasonable to surmise that in the case of humans, longer childhoods (indirectly due to slow-maturing, large, complex brains) led to our pair-bonding inclinations. It’s very beneficial for us to have two caregivers, while Bonobos do fine without this setup. As you point out, other species, such as voles, may become pair-bonders due to other flukes of evolution, but that hardly negates my suggestion about why humans are likely to have ended up with a tension between these two programs.

So why are our brains different and why does it matter? Because our reward circuitry is set up differently from the reward circuitry of a Bonobo. And there’s some evidence that this mechanism makes our brains more sensitive in some important respects. It may, indeed, help explain why we are experiencing more depression, anxiety and addiction as our pair bonds become more fragile. We’re looking elsewhere for rewards we once found through a different, more stable lifestyle.

Personally, I think our brains evolved for tribal life and short-term pair bonds. However, I believe that once we understand more about how our reward circuitry functions and what soothes and balances it, we can consciously learn to create longer, more harmonious romantic bonds. We can steer for greater well-being rather than merely serving our genes. This new behavior may prove critical to our brain-chemical balance, and happiness, now that many of us are without tribes. (More in future posts.)

Hi, and thanks for responding. I'm sorry you feel I didn't respond to your main point, concerning differences between bonobo and human brain structure. I think I did. As I wrote, your argument seemed to be that pair bonding was associated with the development of the neo-cortex in human beings. To repeat, there's no evidence for this, and a great deal of evidence against it.

You write that humans have a "pair bonding program." What's a "program?" The brain is not a computer. It has no programs. The world is full of individuals and cultures where pair bonding is nothing at all like it is in the contemporary Western world. While we're on defining terms, "promiscuous" has a meaning that goes far beyond simply not pair-bonded, as you must know.

You seem to have a lot of theories as to why humans are as they are, but I don't see the connections between the evidence you cite and the theories you propose.

And, I might add, you didn't respond to my main point, which was that your mischaracterization of bonobos was way off the mark. They are, in fact, non-violent, highly intelligent, hyper-social mammals. So the most interesting question, the one I raised in my first post on bonobo bashers, is why? What's the psychological or emotional pay-off you get in pretending to debunk the "utopian" data on bonobos?

"The world is full of individuals and cultures where pair bonding is nothing at all like it is in the contemporary Western world."

Configurations of romantic, sexual, and familial relationships seem to be dependent on where you are geographically, historically, and culturally. Only one thing is certain: some people are monogamous, and other people thrive in non-monogamous relationships of varying configurations, and it's when one configuration is treated as the only acceptable way of doing it that you get trouble.

Human behavior varies a lot. As compared with other primates, we're definitely more influenced by culture, religion, family upbringing, etc. However, we do also have a pair-bonding program. By "program," I mean that our brains are set up in a way that makes pair bonding an inclination in us, in a way it is not for non-pair-bonders. This is a physical phenomenon, not a cultural one.

Obviously, culture and other influences impinge upon this program, but it still exists. The same is true of the program behind the Coolidge Effect and the program that bonds infants with caregivers. Lovers can grit their teeth and choose to remain faithful, even when the Coolidge Effect is urging them toward novel partners, and mothers sometimes do not bond with kids (if, for example, drug use has shifted their neurochemistry for the worse).

It is apparent that humans “have” powerful parent-child bonding programs/inclinations (on average), even if they choose not to have children. Similarly, people may choose never to engage in sex and orgasm, but groups of interconnected neurons are there, ready to give them a powerful experience if they do. It is the same with the Coolidge effect and with pair bonding. These programs are present because of physical structures in the brain. They don’t just happen in a vacuum, and they often influence our freewill in subconscious ways.

We're suggesting that pair-bonding mammals (unlike Bonobos) all share certain basic neural correlates: neural networks, receptor type and specific neurotransmitters, etc. This makes their limbic systems *inclined* (on average) to pair-bond, at least for a time, all things being equal. We're pointing out that this apparently also makes them more sensitive to addictive substances, probably because this pair-bonding program runs on dopamine sensitivity (as opposed to the actual process of pair-bonding). Therefore it is susceptible to any dopamine-raising activity.

Whether a particular human chooses to pair up for life or pollinate many flowers without pairing up, s/he still has this pair-bonder's brain, which is extra sensitive to dopamine, among other things. “Social attachment (pair bonding) and substance abuse share a common neural substrate.” Amphetamine effects in microtine rodents. This has major implications in areas of life that have nothing directly to do with love lives.

Again, the brain has evolved with certain physiological attributes, which have served our genes in the past, across populations, regardless of cultural variations. One of these "programs" comprises the unique physical changes that occur in pair-bonder's brains. Not only is there evidence of physical changes in pair-bonding voles, but there is also evidence of them in pair-bonding primates. See, for example, Neural correlates of pairbonding in a monogamous primate

It's easy to look around and point to cultural variety and promiscuity and say, "See, monogamy is purely cultural." But this is a very incomplete picture. There would not be so much pairing up across so many cultures if there weren't neural correlates behind this behavior. We truly would be like Bonobos…and we certainly wouldn’t be having this discussion. It is equally obvious from levels of human promiscuity that there are neural correlates behind the tendency to add mates as well. However, it's lopsided to argue that we need only look to our promiscuous genetic cousins for an understanding of our mating habits and vulnerabilities.

We have the wiring for all these behaviors. The tension between them often leads to heartache and stress. But, it obviously leads to greater genetic success or we wouldn't be stuck with this tension. Personally, I think we can use subconscious behavioral cues to steer toward different "mixes" of these two programs. We'll see what you think of my theory when I post my thoughts. *chuckle* The point is that we can't even focus on techniques that "speak to" the subconscious mechanisms of the limbic system if we're in denial that we have them.

I'm not arguing "for" or "against" monogamy, or denying the breadth of human experience in any way. I'm simply saying we may be more vulnerable than we realize because of our pair-bonding wiring, and that we may have options for coping. (More soon.)

Now, I hate picking on anyone's cherished totem, but however wonderful Bonobos may be, they have been found to be quite violent with their neighbors. It was this phenomenon I was referring to, which is why I posted this link: "Bonobos not all peace and free love" http://www.telegraph.co.uk/scienceandtechnology/science/sciencenews/3353... (Perhaps you didn't realize the link was there. I'm still learning PT's system.)

Just to clarify, again, I was not suggesting pair-bonding occurs “in the neocortex.” It relies on the reward circuitry (mesocorticolimbic reward pathways, which include, at a minimum, the prefrontal cortex, nucleus accumbens and ventral pallidum). I still think it’s fair to suggest that humanity’s increasing skull size and extended childhood were probably the selection pressures behind our fragile bonding program.

From a Bonobo friendly site, Bonobo Handshake -
http://bonobohandshake.blogspot.com/2008/07/bonobo-violence.html

I got this question from Karenhappywoman, and its a very good one:

Hi, What a beautiful blog! I hope you don't mind me having a little question regarding bonobo's. In your blog as well as in many commentaries about bonobos we see that they are very peaceful and friendly beings. My husband told me that he read an article in which researchers said they have found that many bonobos have missing fingers that were bitten of by other bonobos during fights. Have you noticed any of this and could this mean that not all of their conflicts are resolved by having sex? Thank you very much in advance!

There is violence in bonobo society. A few years ago, five females ganged up on a male called Tatanga and beat the crap out of him, almost ripping his testicles off. the difference between bonobos and chimps is that this violence in chimps is a lot more frequent, and also, violence in chimps can end up with someone dead, whereas no one has ever seen bonobos kill each other.

Kanzi, the really famous bonobo, bit two of Sue Savage Rumbagh's fingers off. Jane Goodall is missing a thumb. Two very good reasons why bonobos and chimps should be illegal as pets!

I

... that bonobos and chimps should never be kept as pets. That an animal is capable of violence doesn't justify calling it a violent animal. Some New Yorkers mug people, but it would be unfair and inaccurate to say, "New Yorkers are muggers."

Just finished reading an interesting piece in Newsweek about evolutionary psychology and the "wiring" of brains. The article ends with these lines:

"Evolution indeed sculpted the human brain. But it worked in malleable plastic, not stone, bequeathing us flexible minds that can take stock of the world and adapt to it."

Link to article: http://www.newsweek.com/id/202789?from=rss

Christopher, your thoughts have been helpful because I now see the need for posts that fill in some of the necessary information about mammalian brain systems, neurotransmitters, receptors and neural circuits. I'll do that back on my blog, but I'll also respond to your assertions here, just to complete our exchange. I can appreciate that you're very busy just now. My own book comes out Tuesday.

First, some readers may believe I'm claiming that that humans are programmed for monogamy (sexual exclusivity). I'm not. I'm saying that we, like the 3% of pair-bonding species, have a neural network for pairing up - with larger implications for the balance in our reward circuitry regardless of what we do in our love lives. If we didn't, bonding simply wouldn't occur. People wouldn't ever be in love with that special someone...or longing for a soul mate. Romance may seem like a product of human invention. However, if a pair-bonding animal loses a mate, it shows measurable signs of stress...and would probably head for the bar if it could.

Yes, the brain is very plastic and many factors and life experiences mold it. It changes in response to mating, pregnancy, caregiving, childhood trauma, drug abuse, etc. However, this does not negate the existence of pre-set neural systems. Again, these produce inclinations; they don’t guarantee behaviors. We tend to love falling in love - and fooling around on the side – because of the tension between our bonding and mating inclinations (programs).

Because tendencies are physiological realities, it pays to become aware of the agendas our genes have instilled in us. Otherwise we can be at the mercy of these programs – and the tensions between them - without realizing what is driving us, what our options are, or how to go about steering for the results we consciously want.

The Coolidge Effect is a program, found across many mammal species, run by the same neurotransmitters, and activated by sexual satiation. I will post more about it on my blog, but here I will just say that the notion that male and female brains (notice, I’m not saying “behavior”) are vastly different appears to be overstated in the case of pair bonding. At its core, in both sexes, pair bonding is rewarding because of dopamine rising in the brain’s reward circuitry. (Other, neurochemicals, such as oxytocin and vasopressin – which do have gender-specific roles in the pair-bonding program of voles - seem to make specific partners rewarding. This happens because they activate dopaminergic neurons in very specific portions of the reward circuitry.)

As you may know, the Coolidge effect occurs due to neurochemical changes. A decline in interest in a partner is associated with lower and lower levels of dopamine. An increase in vigor (when a novel partner shows up) occurs due to a rise in dopamine in the reward circuitry (primarily the nucleus accumbens). This happens in both males and females, although other factors also shape partners’ choices - behavioral and cultural, and no doubt, biological. For example, there’s a link between dopamine and testosterone, which makes you guys more consistently proceptive sexually – and possibly more likely to satiate yourselves sexually.

In response to another of your comments: Cross-species and even cross-class generalizations are not as problematic as you surmise. As my husband says, “Scientists aren’t doing experiments on rats to help them with their addictions and erections.” They’re doing them because all mammalian limbic systems (home of the pair-bonding and Coolidge effect programs) have so much in common that what researchers learn from studying other mammals is generally relevant for us, too. In other words, many, many neurochemicals and their functions appear to be extremely similar in all mammals. Similarly, the pair-bonding mechanism appears to be consistent across the few pair-bonding species – so far at least.

To continue, of course serotonin and dopamine are present in other mammals. Even in the human body, these, and countless other neurotransmitters and hormones, perform many, and surprisingly varied, functions. This is not directly relevant to the issue of pair bonding neurochemistry.

Just to clarify - what I said about Bonobos is that people can no longer boast about their nonviolence in the way they once did. I stand by that statement. Bonobos may be less violent than other chimps, and that is an interesting observation, but it doesn't make them "peaceful" in objective terms. Also, by "neighbors" I meant their "primate cousins," as I said in my initial post, not their troop-mates (with whom they apparently also sometimes fight). Specifically, they kill and eat monkeys. I hope we're all clear on that subject.

By the way, my husband and I loved your fly post.;-)

Wish you the best with the book, and I'll keep an eye on your future blog posts, to see how you clarify these issues around brain systems and so on. For me, appeals to "brain wiring" and "behavioral programming" are highly suspect, in that there is no hard wiring or programming in the brain. It's a bit like arguing the face was designed for eye-glasses because the nose and ears are so perfectly placed.

But maybe your book will convince me I'm wrong. Stranger things have happened.

CPR

QUOTE: "For me, appeals to "brain wiring" and "behavioral programming" are highly suspect, in that there is no hard wiring or programming in the brain."

I srongly disagree, In fact, there's plenty of hardwiring in the brain - just a few examples:

1- The brainstem contains multiple autonomic reflexes, such as digestion, heart rate, respiration, fight or flight, etc.

2- Further up in the limbic system, the hypothalamus has multiple nuclei that when stimulated lead to very specific, yet more complex functions, such as: Hormone production and release; regulation of body temperature; senstaions of hunger, thirst, satiety; regulation of sleep/wake cycles; and yes even production of emotions and behavioral drives.
Stimulate the above centers and one gets a very specific outcome. Is that hardwiring?

We can consciously use other parts of our brain to amplfy or to ignore some of these very powerful signals - such as ignoring hunger, or trying to stay awake. But these "programs" will continue to prod us to eat or sleep.
In other words, just because we don't observe a behavior doesn't mean a program is running in the brain urging them to do something. Maybe they are starving, but are on a diet; maybe they are sleepy but driving a car; maybe they want to punch a bully, but they are outweighed by 100 pounds of muscle.

As for "brain wiring", it is the basis of nearly every function of the nervous system. All reflexes are wiring, all learning is wiring, as is the specialized functions of specific brain regions. What nervous sytem function is NOT based on groups of inerconnected neurons working together?

The common wiring and brain centers found in all mammals is what neuroscientists study when experimenting on rats, primates, sheep, etc. Analagous structures with analogous functions. If it's highly suspect, then neuroscientists must be barking up the wrong tree.

The connection between addiction and pair bonding via dopamine, as Mrs Robinson proposed, is extremely far fetched. Of course both behaviors have some fundamental neural mechanisms in common as "liking", "seeking", or "learning", but these connections are so unspecific that this fact is rather meaningless. You are using your dopamine pathways when you're reading this as well as when you are going to the bathroom.
I am sure Mrs Robinsons book will explain a large part of human behavior in a way that solves many fundamental question we have been asking ourselves, with simple, easy to understand explanations that have no unnecessarily limiting roots in actual science.
It's quite obvious what kind of ideology she is trying to push.