Tag Archives: behavioral biology

Aging in men: An evolutionary perspective

Many years ago, Mel Konner, Marjorie shostak, and Boyd Eaton wrote “The Paleolithic Prescription: A program of diet and exercise and a design for living.” (It is hard to find these days. To find it and related titles on Amazon, look for this book first, and track the PP down via the author name Konner.)

(Added: You can probably get the The Paleolithic Prescription here.)

Richard G. Bribiescas is professor of anthropology and ecology and evolutionary biology at Yale University, where he also serves as deputy provost for faculty development and diversity. He is the author of Men: Evolutionary and Life History. He lives in Hamden, Connecticut.
Richard G. Bribiescas is professor of anthropology and ecology and evolutionary biology at Yale University, where he also serves as deputy provost for faculty development and diversity. He is the author of Men: Evolutionary and Life History. He lives in Hamden, Connecticut.
That was the first “stone age” diet book. But, it was different from all the others, and the only one worth anything. Mel and Marjorie were two of several individuals, including my advisor and theses readers, Irv Devore and John Yellen, who engaged in the famous Kalahari Project, in which the biology and lifeways of the Ju/’hoansi foragers (aka Bushmen or San) were studied intensively for several years.

The researchers noticed that there were differences in lifeways between these exemplary foragers and industrialized people’s of the West that seemed related to health and well being. They were able to link, sometimes definitively, sometimes tentatively, diet and activity levels on one hand and health on the other. Their findings, by the way, were first published in the peer reviewed literature, then turned, by the scientist themselves, into a popular book. (One of the findings eventually led to the understanding that there are different kids of cholesterol, which seem to have very different health related implications.)

My own research with the Efe (Pygmies) of the Ituri Forest, in Zaire, was an indirect offshoot of that early work. I got my PhD at the same institution, Harvard’s Anthropology Department that housed much of the Kalahari project, and the Ituri project was started by the same leader, Irv DeVore, via his students. So, the tradition of examining the lifeways of modern day foragers, in part to understand ideal human conditions, and comparing those conditions to western ways continued.

Meanwhile, one of the graduate students at Harvard, Peter Ellison (yes, he is related to that Ellison) had been interested in some work coming out of Harvard Medical school looking at hormones and behavior, especially as related to reproductive biology of human women. Building on that work, Ellison created an entirely new field of study, called “Reproductive Ecology.” He finished his PhD and was added to the faculty at the Anthropology department in one of those in between positions (as was I and many others over the years) but Peter became one of the very few such individuals to be eventually offered a tenured position with the most “always hire from outside” institutions ever. And Ellison created the Reproductive Ecology Lab within the biological anthropology wing of Harvard’s Department of Anthropology.

screen-shot-2016-10-24-at-11-01-54-amAnd, they studies the heck out of female reproductive ecology. I had the pleasure of working, almost every semester that I was there from late in my PhD cycle through my post-PhD teaching career there, to work with Mary O’Rourke (and others) who were from that lab running an undergraduate tutorial. The tutorial is three or four faculty members each running two or three groups, with about five or six students in each group. These are students majoring in Biological Anthropology, who have already taken a class or two but are on their way into the research labs. The tutorial instructors’ job is to turn these young and interested minds into the minds of proto-Anthropologists by carefully examining a different topic each week, looking at a combination of peer reviewed literature and secondary but excellent literature (back in those days, the former was easier to find).

So, I spent a lot of time hanging around with the Reproductive Ecology people (and, by the way, collecting some of their data in Zaire). Every social event had a lot of Repro Eco folks at it, so it was pretty normal for someone to pull out a box of specially prepared test tubes to get every one to provide saliva samples for some study or another. It was not long into the process of developing this subfield that the reproductive ecology of men, simpler but still important, was also taken up by this group, so everyone had an opportunity to spit into the tubes. For example:

Hypothesis: Testosterone in men varies over short time scales (of minutes, hours) during a poker game depending on which cards they are dealt, assuming the samples are not contaminated by …

… oh, never mind, you get the picture.

Anyway, it was while I was a couple of years into my own graduate career when a young man from California showed up to study anthropology, with a particular interest in Biological Anthropology. It was Richard Bribiescas. Rick and I did not hang around a lot of time, because we were both busy, but we were good friends and broke bread (a euphemism for guzzling beer but there were also tacos and cheeseburgers) quite often.

When Rick got to Harvard, there was already a strong tradition of working to understand modern human problems in the Western world by examining modern human behavior and physiology in a variety of other societies, including foragers.

Many young men and women went to the field from that department, to work in Poland, Borneo, the Amazon, the Congo. Among those, very few attempted to work in the most difficult of conditions, in a rain forest with foragers. Of those who tried most retreated and picked another topic. A few persisted and continued to study this or that thing about one of the few remaining forager group son the planet. That’s what I did, with the Efe. That’s also what Rick did, with the Ache, of South America.

And, as a result of that, Rick produced a bunch of interesting peer reviewed papers, and eventually, a book that has been out for a while now called Men: Evolutionary and Life History. A number of books had been written about female reproductive ecology, but along the way, rick became the expert on male reproductive ecology, discovering that it is not as simple as one might expect. This book is the result of that achievement.

And now, Rick is an old guy. He must be at least 45. And, as such, he has turned his attention to a new but related topic: How do men age. And, the newly produced book that comes from this research to your book shelf is How Men Age: What Evolution Reveals about Male Health and Mortality

Do not buy or borrow some book on aging written by a web site, a fake MD, or some other charlatan. Read a book on aging (in men) that first appeared many times in the peer reviewed literature, written by Harvard Trained Yale Expert Richard Bribiescas.

Note the subtitle. This is about what evolution reveals about male health and mortality. Having taught along side him many times, and after all those beers, tacos, and cheeseburgers, I can tell you that Rick knows all about evolution, and of course, he is the world’s leading expert on male reproductive ecology.

I put the Table of Contents below to give you and idea.

Rick is a great writer, and this book is fun to read.

Do the well known features of male aging have some sort of evolutonary advantage, as has been proposed for females? How much of male aging in the West is a function of our Western lifestyle, or a function of our seemingly extended lifespan? What about the contradiction between what we mere humans think of as “health” or “healthy” and what the cruel and cold process of Darwinian natural selection things about such silly things? What about sex, relationships, monogamy, polygamy, fatherhood and child rearing, in male humans in general, and across the aging process? And our brains, our obscenely large brains, what the heck are they for?

You will enjoy this book, especially if you are a man of a certain age.

Table of Contents:

Acknowledgments ix
Chapter 1 A Gray Evolutionary Lens 1
Chapter 2 Dead Man’s Curve 17
Chapter 3 Getting a Handle on Love Handles 45
Chapter 4 Older Fathers, Longer Lives 70
Chapter 5 Dear Old Dad 88
Chapter 6 Darwinian Health and Other Contradictions 106
Chapter 7 Older Men and the Future of Human Evolution 133
Notes 145
Index 169

A kiss is not a kiss…

The authors of a new paper note that “one of the principal ways in which we interact using our faces is kissing.” This reminds me of an old National Lampoon joke on how the French were famous for inventing sex acts with the face. But I digress.

This paper looks at neural imaging responses of subjects who observe, in photographs, various kinds of kissing. The two main variables are who is kissing (by gender) and the nature of the kiss.

One of the authors is my friend and colleague, Sheril Kirshenbaum. She wrote the book on kissing. No, seriously, she wrote this book, which I’ve reviewed here.

From the abstract of the paper:

With a few exceptions, the literature on face recognition and its neural basis derives from the presentation of single faces. However, in many ecologically typical situations, we see more than one face, in different communicative contexts. … Although there is no obvious taxonomy of kissing, we kiss in various interpersonal situations (greeting, ceremony, sex), with different goals and partners. Here, we assess the visual cortical responses elicited by viewing different couples kissing with different intents. The study thus lies at the nexus of face recognition, action recognition, and social neuroscience. Magnetoencephalography data were recorded from nine participants in a passive viewing paradigm. We presented images of couples kissing, with the images differing along two dimensions, kiss type and couple type. We quantified event-related field amplitudes and latencies. In each participant, the canonical sequence of event-related fields was observed, including an M100, an M170, and a later M400 response. The earliest two responses were significantly modulated in latency (M100) or amplitude (M170) by the sex composition of the images (with male-male and female-female pairings yielding faster latency M100 and larger amplitude M170 responses). In contrast, kiss type showed no modulation of any brain response. The early cortical-evoked fields that we typically associate with the presentation and analysis of single faces are differentially sensitive to complex social and action information in face pairs that are kissing. The early responses, typically associated with perceptual analysis, exhibit a consistent grouping and suggest a high and rapid sensitivity to the composition of the kissing pairs.

Interesting research, part of the bigger picture of how human perception operates in an important social context. I asked Shiril Kirshenbaum for a quick comment and she told me that one of the most interesting parts of this work is “that usually we think of science writing as something that happens after research or discovery. But here we have a nice example demonstrating that the relationship can go both ways where new science has been driven by the storytelling.”


A kiss is not a kiss: visually evoked neuromagnetic fields reveal differential sensitivities to brief presentations of kissing couples. 2015. Cogan, Gregory, Sheril Kirshenbaum, Jeffry Walker, and David Poeppel. NeuroReport, August 18, 2015.

Do genes make you gay?

Of course they do. To the extent that genes make you anything in particular, though the role of genetics in human behavior is pretty limited.

You’ve probably heard about the newly reported research in which a genetic link was found to homosexuality in a study of gay brothers. Kelly Servick has a good writeup on it here. The study looked at 409 pairs of gay brothers, and found a region on the X chromosome that was similar across the sample. This sort of shotgun approach, comparing a trait (in this case, gayness) with a bunch of DNA (I oversimplify) is very likely to get results that look real but are the result of random association. But, it is also possible to find real links. I am agnostic as to whether or not this study found something interesting. But I do have a few remarks to make about how you get to be gay.

Consider the following list of things:

<li>Sexual attraction (to whom you are attracted)</li>

<li>Erotic response (what is erotic, including physically, to you)</li>

<li>Attachment (with whom to you seek attachment, and of what kind)</li>

<li>Sex drive (do you have it and where is it driving too?)</li>

<li>Society norms (especially for your subset of society)</li>

<li>The details of social norms, i.e., what categories of sexual orientation exist around you.</li>

<li>Your relationship to social norms (your comfort level ... do you seek "normalcy" or prefer something else?)</li>

<li>Whom you know or encounter and where they are with all of the above things.</li>

<li>And many more things that ultimately may relate to sexual orientation.</li>

This list can be written in many different ways, and every item on this list really represents a number of other sub items. These things are not mutually exclusive and the list is not exhaustive of that which relates to sexual orientation. Feel free to provide your own lists in the comments, if you like.

Many, most, maybe all of these things have individual ontogenies for any individual. The ontogenies may start before birth. We are bathed (or not) in various maternal hormones in utero. We are bathed in our own hormones in utero. The effects the hormones have depend on the relationship between the amount of hormone and the abundance and distribution of receptor sites, and on the timing. The abundance and distribution of receptor sites itself is probably influenced by the process. It is very complicated. Differences between one individual and another may related to external or non-genetic factors. In fact that may be very common.

Hormonal effects and interactions continue after birth. Again, timing, relationships between kinds and relative amounts of hormones, and receptor sites, still apply. Causes may be numerous.

The above only applies to that related to hormonal changes, which may affect a number of somatic (body related) features including brain features.

Then there are the non-hormonal factors, including cultural and social ones. Again there are complexities to the ontogeny of an individual with respect to these factors. And, these complexities are dynamic; culture and society can change right underneath you. And the non hormonal and hormonal factors may interact.

Much of this can be thought of as a process of negotiation. One negotiates internally, one negotiates with one’s social groups, one negotiates with society, culture, even the law.

Here is a simplified model linking the DNA identified in this study to homosexuality. Various switches are turned on or off, buttons pressed or not, during a person’s development. They do everything in some individuals to “make a person be gay.” But there is one element missing. If you have the DNA profile associated with the sample of 409 brothers, you get to be gay. If not, you probably won’t be. But, the “yes-no” value (reminder: oversimplifying here) found in this DNA actually has another purpose. It has to do with how many hairs you have on the back of your hand. The variation across men in hand hair is accounted for by variation in these genes. But in some individuals (but not all) it also happens to be the final ontogenetic link in the chain to a particular sexual orientation that in the sociocultural context that the 409 pairs of men live in results in gayosity. In another society, another culture, at another time, it results in being more likely to be a blacksmith than a farmer.

Note: That was a made up example. But in the absence of a biologically, developmentally, sensible link between some DNA and a trait, we can certainly carry out amusing and instructive thought experiments.

This complexity of links between causes and effects is probably true for the vast majority of variation found in human behavioral traits. Not this exactly, but something like this. The steps involved can be characterized in a certain way with respect to a trait under study, but all or most of those steps actually relate as well to other things. Also, some of those steps might have multiple causes. A particular manifestation of sexual or erotic attachment may arise in one person for one reason, in a different person for a different reason. In other words, the list I provide above can take many forms, not just because I’m being vague about what is in the list. The list can simply be different for different people who end up with the same “trait” as we happen to define the trait for the moment.

There is a reason for this vague connection, or in many cases, lack of connection, between inherited genes and behavior. A strong link between genetics and behavior has been shown to be very highly adaptive in some organisms. Here’s an old example. In a particular species of fruit fly, the larvae have a gene with two alleles. One allele causes the larvae to forage tightly in space, making a lot of turns in its search for food. The other allele causes the larvae to forage widely, to make few turns, and cover a larger area. Each allele is adaptive in a particular context and the fruit fly species has diversity at this locus. So, the fruit fly female mates with multiple males, produces a diverse batch of offspring, and the ones with a particular pattern of alleles at that locus have higher fitness. For now. In a different environment, maybe a few generations later (as the orange juice they are feeding on changes its characteristics as it rots in that glass you left on your desk) the genetic arrangement with the higher fitness changes.

But, humans are different. Humans are like the fruit fly, needing different traits at different times, but instead of those traits being programmed by genes, they are learned. Added on to the individual by enculturation.

This applies to some extent to all mammals because mammals have brains that matter to behavior. It applies very much so to primates, especially apes, and even more to humans. We have diversity in behavior, but we get it from our cultures. We learn to be a functioning adult; it is not pre-programmed. There probably are some pre-programmed behavioral features, but those are the features that would generally apply. But even those may be largely divorced from genetic inheritance on the grounds that behavior generally does not emerge from genes coding for neural structures. Genes in humans can’t code for neural structures at the level of the cerebrum, because of the way cerebrum develops, and that is where most of the relevant behaviors exist.

We can be pretty sure this is the case because of the huge cost we pay for it. Childhood. Childhood may be the most important human adaptation, and it may be the most costly. Human females can die in childbirth. That is nearly unheard of among mammals, outside of humans and our domestic stock. The babies can die in childbirth as well. That is because of our oversized brainy heads. Human babies are born helpless and spend several years nearly killing themselves at an alarmingly high frequency, and only survive childhood because of the adult humans taking care of them (or in some cases, wolves or ocelots, I suppose). This is costly to the adults. It limits reproductive output in the adults. Childhood also limits the reproductive output of the child, because it extend the time before reproduction, and decreases the chance of survival until reproduction.

Childhood, a brain that learns, the heavy reliance on the things the brain learns, and the long time it takes to make all this work demands a brain that is not overly programmed genetically, and results in a species with an extraordinary characteristic found in no other species: we are a multitude.

If you look at numerous species in most mammal families, you will find a wide range of behavioral and ecological repertoire. Measure body size, sexual dimorphism, typical system of mating, food getting, diet, defense, inter and intra species competition, etc. across all of the geomyids or voles, across all the species of dogs or all the species of cats, across the antelopes, across the African forest monkeys, etc. and you’ll find many features such as those mentioned that vary very little within species, but vary greatly across them within that taxonomic group.

Then look at humans. They look more like a taxonomic family than a species. Human cultures vary in these and other features as greatly as larger mammalian taxonomic groups.

But, when you capture an infant at birth from one human group and have it raised by another group, the infant grows up with behaviors typical of the adoptive group, not its natal group. That pretty much falsifies the idea that variation in our behavior is linked to variation in our genes.

By the way, if you move new born antelope, rodents, primates, etc. between species you may get some of the same effect. Cross species adoption does result in a bit of a behavioral chimera sometimes. But, it is only possible between some species and tends to work when the interactive parts of the system happen to be aligned. A parent bird will feed mouth-gaping carp for a while if they’ve lost their mouth-gaping baby birds. Within mammals, we’d expect a fair amount of post adoptive learning across species, because, as I noted above, learning how to be typical member of your species applies to some degree to mammals in general, more so to primates, more so to apes, and vastly more so to humans. Vastly.

Imma let you get back to finding links between genes and behavior. But first, remember, culture rules.

Final note. Part of the reaction to this new research, and this has happened with all prior research on homosexuality, is in reference to the sociopolitical outcome. If you are born gay, Conservatives can’t legislate against you, but if it is a choice, you might be a criminal. That sort of thing. This is balderdash. The Nazi’s killed all those people because of their genes. Many value free choice. Some will see being born gay as being born broken. People who are born a certain way, in many sociopolitical contexts, are vilified for it. You can’t win the sociopolitical game by claiming a certain human behavior or trait is built in or choice. You win that game on its own terms. And, lately, we mostly are winning.

Baby Cries Cause Concern For Mothers Of Other Species

It has long been known by humans that female mammals can be attracted with the call of a young in distress. There is a famous documentary film of the Hadza, a foraging group in Tanzania, in which this method is used by young boys to trap Dasssies (rock Hyrax). First you catch a baby Dassie (not hard) then you hid and bit it in the neck so it cries out, then when the momma Dassies come to rescue it you shoot them at short range with an arrow or whack them with a stick. Adult Efe Pygmy hunters sometimes imitate the call of a young Duiker (a forest antelope) in distress in order to draw in females. I’ve spent a fair amount of time hanging around with adult male Efe hunters and never saw this work, but they claim it does and I tend to believe them.

Now, researchers have demonstrated cross-species response to distress calls by young. They recorded distress calls by various mammals such as seals, dogs, cats, and humans. Never mind how they got the distress calls. Anyway, they played these for White Tailed Deer females and got a response. The mother deer moved towards the recordings. These baby mammals all have similar pitched calls. The researchers also recorded bats and lowered the pitch to be within that range, and the deer responded to this as well.

Presumably there is strong selection on responding to distress calls of young, but not strong selection on being selective, probably because the circumstances do not arise that often.

More here.

Is Human Behavior Genetic Or Learned?

Imagine that there is a trait observed among people that seems to occur more frequently in some families and not others. One might suspect that the trait is inherited genetically. Imagine researchers looking for the genetic underpinning of this trait and at first, not finding it. What might you conclude? It could be reasonable to conclude that the genetic underpinning of the trait is elusive, perhaps complicated with multiple genes, or that there is a non-genetic component, also not yet identified, that makes finding the genetic component harder. Eventually, you might assume, the gene will be found.

That is probably true sometimes. But we have sequenced the entire human genome, so shouldn’t we know about all the genes? Well, yes and no. We may have a list of genes found in a sample of humans, but “The Human Genome” can consist of a single individual (though it does not) and miss variation between individuals, i.e., it may not be a record of all of the possible alleles (variants) of each gene. Also, beyond the scope of this discussion but worth mentioning, a “gene” is not a simple concept. Whether or not a gene is expressed, where, when, and exactly what product it produces is not entirely encoded in the gene itself, but rather, elsewhere in the genome, or not encoded at all, but rather, dependent on external, non-genetic factors. So that complicates things too. So, if there is a trait that you think must be genetic, but years of research have failed to find it, the existence of a human genome and the prior acquisition of a lot of genetic data does not necessarily mean that the genetic information that determines the trait in question is not there. You can continue to believe that the genetic code for the trait will eventually be found

Except when you can’t.

There are two separate ways in which people sort out which traits are assumed to be genetic from those that are assumed to be not genetic. Both are heuristic, one is valid, and one is not. Let’s start with the one that is valid.

Suppose, as before, there is a trait that is seemingly inherited in families in such a way that a genetic trait would be, in the time tested manner that with respect this trait “offspring resemble their parents” as Darwin noted. The next question you can ask is this: Is it biologically sensible that this trait is inherited genetically, or is there a better, obvious, non-genetic mode of inheritance? If the trait is a physical feature such as eye color, then we have a sensible biological explanation for the trait having to do with developmental process we know something about and a set of metabolic pathways that produce various molecules such as pigments. The idea that this trait is genetic is biologically sensible, so even if you can’t find any, or all, of the genetic determinants of this trait, you can figure they are out there somewhere. Suppose, though, that the trait is a behavioral one that we see people in real life learning. For example, what language a person speaks generally follows the same kind of inheritance pattern many clearly genetic traits follow. With respect to spoken language, most of the time, offspring resemble their parents. But, rather than there being a sensible biological explanation for this trait, there is a sensible cultural explanation for this trait, so we don’t even look for the genetic variants for “French” vs. “Mandarin” vs. “English.” We simply assume this is not genetic.

The second method, the incorrect one, is to work with an article of faith. Broadly speaking, and I oversimplify greatly here, there are two primary articles of faith that often inform people’s thinking, shaping their assumptions, about genetics. Both usually have to do with behavioral traits in humans, but this can apply to physical traits as well. One article of faith asserts that humans are born as a blank slate, and all of their behavioral characteristics, such as their personality, intelligence by one measure or another, and so on, are added by experience. The other is the inheritance assumption, that some or much of an individual’s personality, intelligence, etc is determined by genes. There is not necessarily a consistent logic behind either of these assumptions, though various schools of thinking will include, often, a logical framework. However, this method of coming to a conclusion about the genetics or lack thereof behind various traits relies on one important element regarding genetic systems: Ignorance. If you are a blank slatist, then the absence of a clear pathway from genes to behavior means that your hypothesis can’t be falsified. If you are a genetic determinist, then the lack of such a pathway can be attributed to ongoing ignorance about the genes. The former might then be expected to live in fear that a gene will be found for their favorite learned behavior, and the latter might be expected to to live in a state of hubris, firmly knowing and asserting a truth that is not yet known but someday will be.

My impression is that over time there are fewer and fewer pure genetic determinists out there, and few and fewer blank slatists. I think the reasons for that shift have little to do with increasing knowledge, and more to do with changes in how one plays the academic game of argument, but that is discussion for another time. There is a danger in that shift, though. In the absence of any useful research results, if blank slatists start to admit that there could be some sort of genetics behind behavior, and determinists start to admit that experience and learning can also play a role, then we are converging on an increasingly simplified view of what is really a very complicated process. We should be gaining more complex, nuanced, and better informed views of how behavior arises, not simpler ones. Probably.

Over the last few decades, there have been a few important changes in how we should view human behavior over generational time and variation in those behaviors within and across categories (gender, ethnicity, geography, etc.). In short, certain behavioral traits have shown, synchronically (lacking the perspective of change over time) patterns that look genetic. For example, some families seem to be extra smart. Some have suggested that some “races” are smarter than others (at another time we can discuss why there really are no races, but let’s use “race” here as a potentially valid sampling strategy, which it can be even if the underlying races are fictions). We also see assertions of behavioral differences between the primary sexes (male vs female).

These observations are really statements about variance. Two groups are different, but vary within. There is overlap in the trait (i.e., IQ) but the means vary. We can statistically test the validity of the asserted differences in means by examining the variance in each sample and seeing if the mean of one sample fall within the predicted range of the central tendency of the others. In other words, asserting that there is a statistical difference between two groups is a process that involves understanding the variance of the underlying population(s) and samples. So, the questions can all be reframed in this manner:

Is the variation we see in trait X across certain groups best explained by underlying corresponding variation in the genetic system, or by the variation found in some other cause?

People fight vigorously over the underlying cause of IQ differences between groups. Some say it is primarily genetic, some say it is primarily not genetic, but rather, related somehow to what has become known as “lived experience.” Over the last couple of decades, there have been many attempts to explain observed variation in IQ using socioeconomic status, diet, education, issues having to do with test making or testing procedures. All of these factors have been shown to explain differences between groups to a modest to large degree in several studies. In other words, if you want to explain variation in IQ using non-genetic explanations, you can have some real success.

The genetic explanation of variation in IQ has had success in one main area which is irrelevant. This is the fact that genetically determined developmental differences between people that affect function that are generally classified as disorders predict large IQ differences. But this set of effects is not related to the question being asked.

The strongest evidence for a genetic underpinning of IQ is probably the large scale racial model solidified years ago by J. Philippe Rushton. He demonstrated that there is a grouping of brain sizes by race, with Asians having the largest brains, Caucasians the second larges, and Blacks the smallest (these race terms are his). He then showed that these brain sizes correlated with IQ difference. The modern psychometric literature assumes a racial difference in IQs, and asserts that this difference is real, but does to by citing sources that then site sources that ultimately cite Rushton. Rushtons all the way down, as it were.

The problem with this is that Rushton’s analysis was bogus. The brain sizes were taken from such sources at hat sizes for army conscripts classified by race, with the hat sizes used to estimate brain size. The Black (African) brain got smaller because Rushton subtracted a factor from that estimate of brain size, using an archaic thick skulled African fossil to assume that Africans have very very thick skulls. Correspondingly, the Asians were assumed to have thin skulls, and thus, got larger brains. The IQ data is similarly adulterated. In one part of the study, Rushton needed an “African” (native) IQ value, so he used the results of a test administered by racist anthropologists commissioned by the Apartheid government of South Africa to prove the inferiority of Blacks. And so on. The bottom turtle in this edifice is a fake.

The range of variation across “racial” groups (or other groups) in modern IQ data is very small compared to the change in IQ measured or estimated over decades of time through the 20th century within a single large and diverse population (Americans). If IQ is genetically determined and a stable feature of behavior, then there has been more evolution of these genes over less than 100 years of time in the US than we see across any two groups of modern humans. That is impossible. Again, IQ does not behave nicely as a genetic trait.

The discovery of a gene or set of genes that would underly IQ has not happened. In some recent studies, IQ is assumed to be very complex and the result of many different genes, and there is some statistical evidence for this. But, there is a big problem there too. Any trait can be linked to a set of genetic variants if the set of genes is large enough. That is a statistical effect and it is not really a link. More like a party trick, or a con game. (In fact this method is a con you may have heard of. I send 10,000 people an email predicting that a certain stock will go up, another 10,000 people an email predicting it will go down. One or the other happens. I then send 5,000 of the people who got the “correct” prediction another prediction, and 5,000 of them the opposite prediction. Now, 2,500 people have gotten two correct predictions from me. I keep doing that until I’ve got several dozen people convinced I am a stock market genius, and I take their money.)

Generally speaking, many behavioral traits have been explained, in part and sometimes in large part, by factors that are not genetic, while at the same time, the hunt for the presumed underlying genes have come up empty. There was great optimism up through the 1990s that genetic underpinning of human behavior … genetic variation corresponding to behavioral variation … would be found. But even as early as 1993 this was being questioned. Here is a sidebar, reproduced in full, from a Scientific American article by John Horgan summarizing the work up to that time:

Behavioral Genetics: A lack of progress report (1993)

CRIME: Family, twin and adoption studies have suggested a heritability of 0 to more than 50 percent for predisposition to crime. … In the 1960s researchers reported an association between an extra Y chromosome and vio-lent crime in males. Follow-up studies found that association to be spurious. MANIC DEPRESSION: Twin and family studies indicate heritability of 60 to 80 percent for susceptibility to manic depression. In 1987 two groups reported locating different genes linked to manic depression, one in Amish families and the other in Israeli families. Both reports have been retracted. SCHIZOPHRENIA: Twin studies show heritability of 40 to 90 percent. In 1988 a group reported finding a gene linked to schizophrenia in British and Icelandic families. Other studies documented no linkage, and the initial claim has now been retracted. ALCOHOLISM: Twin and adoption studies suggest heritability ranging from 0 to 60 percent. In 1990 a group claimed to link a gene—one that produces a receptor for the neurotransmitter dopamine—with alcoholism. A recent re-view of the evidence concluded it does not support a link. INTELLIGENCE: Twin and adoption studies show a heritability of performance on intelligence tests of 20 to 80 percent. One group recently unveiled preliminary evidence for genetic markers for high intelligence (an IQ of 130 or higher). The study is unpublished. HOMOSEXUALITY: In 1991 a researcher cited anatomic differences be-tween the brains of heterosexual and homosexual males. Two recent twinstudies have found a heritability of roughly 50 percent for predisposition to male or female homosexuality. These reports have been disputed. Another group claims to have preliminary evidence fo genes linked to male homosexualty. The data have not been published.

This is from a study by Jay Joseph on the “Classical Twin Method in the Social and Behavioral Sciences”

The classical twin method assesses differences in behavioral trait resemblance between reared-together monozygotic and same-sex dizygotic twin pairs. Twin method proponents argue that the greater behavioral trait resemblance of the former supports an important role for genetic factors in causing the trait. Many critics, on the other hand, argue that non-genetic factors plausibly explain these results…. In 2012, a team of researchers in political science using behavioral genetic methods performed a study based on twin data in an attempt to test the critics’ position, and concluded in favor of the validity of the twin method and its underlying monozygotic–dizygotic “equal environment assumption.” The author argues that this conclusion is not supported, because the investigators (1) framed their study in a way that guaranteed validation of the twin method, (2) put forward untenable redefinitions of the equal environment assumption, (3) used inadequate methods to assess twin environmental similarity and political ideology, (4) reached several conclusions that argue against the twin method’s validity, (5) overlooked previous evidence showing that monozygotic twin pairs experience strong levels of identify confusion and attachment, (6) mistakenly counted environmental effects on twins’ behavioral resemblance as genetic effects, and (7) conflated the potential yet differing roles of biological and genetic influences on twin resemblance. The author concludes that the study failed to support the equal environment assumption, and that genetic interpretations of twin method data in political science and the behavioral science fields should be rejected outright.

With respect to psychiatric disorders, from the same author:

The psychiatric genetics ?eld is currently undergoing a crisis due to the decades-long failure to uncover the genes believed to cause the major psychiatric disorders. Since 2009, leading researchers have explained these negative results on the basis of the ‘‘missing heritability’’ argument, which holds that more effective research methods must be developed to uncover presumed missing genes. According to the author, problems with the missing heritability argument include genetic determinist beliefs, a reliance on twin research, the use of heritability estimates, and the failure to seriously consider the possibility that presumed genes do not exist. The author concludes that decades of negative results support a ?nding that genes for the major psychiatric disorders do not appear to exist, and that research attention should be directed away from attempts to uncover ‘‘missing heritability’’ and toward environmental factors and a reassessment of previous genetic interpretations of psychiatric family, twin, and adoption studies.

And from researcher Tim Crow:

A substantial body of research literature, identified by nine out of ten papers on genetics in the recent ISI research front on schizophrenia, claims to have established associations between aspects of the disease and sequence variation in specific candidate genes. These candidatures have proven unreplicated in large sibling pair linkage surveys and a targeted association study. Even if the case for an association be regarded as a lucky guess (assuming one gene in 30 000 was guessed right) the large linkage and association studies provide no evidence of sequence variation relating to psychosis at any of these gene loci. Thus this body of work must be regarded as an indicator of the extent to which the ‘eye of faith’ is able to discern meaning in complex data when none is present.

I could go on. There have been further criticisms of the twin studies, for example. The most interesting, potentially, of these studies was on twins reared apart, more or less separated at birth. Commonalities among such individuals would be strong evidence for a genetic underpinning, because these individuals were raised in completely different environments so there would be no chance of a learned or cultural component other than a general background effect of having been raised n the same planet, or in the same country. Right? Well, no. Twins separated at birth were mostly twins that were not all that separated. After all, where do researchers actually find twins truly and distantly separated at birth, especially in the days when people seeking birth parents had hardly become a thing yet? Many of these twins, probably the vast majority, were separated only in the sense that they were raised by different members of the same family, or separately by divorced parents. Many were raised in the same neighborhood or often, the same house. My brother and I are not twins, but we were “raised apart” by the criteria of the twin studies because my family was distributed among the rooms of a two family residence, so technically he and I had bedrooms at different addresses.

In sum, it is easier to find sociological, cultural, or environmental explanations for variation in human abilities, intelligence, or personality traits. The seeming inheritance by family of some of these traits may well be a combination of something genetic and something experiential or cultural, but when looking for the actual underlying causes, genetics has repeatedly come up wanting while environmental explanations do a good job of addressing a fairly large part of the variation we see. Models of race based differences are so poorly done, and are often highly politically motivated, that they should never be trusted. That scientific ship sailed a long time ago.

Maybe the blank slate theory isn’t so bad after all. It does not imply that just anything can happen when making a human being out of a sperm and an egg. After all, it is a blank slate and not a blank whatever. But it is probably not true that some people’s lived experiences are written on slate, while others on white boards, and still others on smart boards, even if there are some people who I’m sure assume that they were.


Selected references:

Horgan, John. 1992. Eugenics Revisited. Scientific American. June.
Joseph, J. (2011). The Crumbling Pillars of Behavioral Genetics. GeneWatch, 24 (6),4–7. Web page
Joseph, J. (2012). The “Missing Heritability” of Psychiatric Disorders: Elusive Genes or Non-Existent Genes? Applied Developmental Science, 16(2), 65–83. doi:10.1080/10888691.2012.667343
Joseph, J. (2013). The Use of the Classical Twin Method in the Social and Behavioral Sciences : The Fallacy Continues, 34(1), 1–40.
Lewontin, R. Human Diversity. 2000, Scientific American Library.
Marks, J. (2008) Race: Past, Present, and Future. In: Revisiting Race in a Genomic Age, edited by B. Koenig, S. Lee, and S. Richardson. New Brunswick, NJ: Rutgers University Press, pp. 21–38. PDF
Marks, J. (2008) Race across the physical-cultural divide in American anthropology. In: A New History of Anthropology, edited by H. Kuklick. New York: Blackwell, pp. 242–258. PDF
Tizard, B. (1974). IQ and Race. Nature, 247, (5349), 316.


Other posts of interest:

Also of interest: In Search of Sungudogo: A novel of adventure and mystery, which is also an alternative history of the Skeptics Movement.

Whitey Bulger Convicted, and the Trivers Willard Hypothesis

Whitey Bulger has finally been convicted of a small percentage of all the bad things he is said to have done. The Boston Globe has the details.

James J. “Whitey” Bulger, the notorious Boston gangster who rampaged through the city’s underworld for decades before slipping away from authorities and eluding a worldwide manhunt for more than 16 years, was convicted today in federal court of charges that will likely keep him in prison for the rest of his life.

Don’t count on that. Whitey has slipped from the clutches of justice several times before. He’ll probably make a break for it between the court house and the jail, and if not, he’ll break out by pretending to be laundry or something in a few weeks.

Anyway, I started making references to Whitey Bulger back when he was just … retiring … and I live in the Boston Area, because he provided me with a good analogy in teaching about behavioral biology. So, whenever Uncle Whitey gets in the news I like to repost that. So …. from an earlier post (which still refers to him as a fugitive) we have this ….


Thumbnail image for 0470656662.jpgThis may or may not be a recent photograph of fugitive Whitey (James) Bulger of Boston’s Winter Hill Gang. Most of you won’t know who Whitey Bulger is. He is actually on the FBI’s ten most wanted list. He may have been spotted in Italy last Spring, and the FBI is just now asking for assistance from anyone who knows where he might be. (That’s not gonna work.)

Whitey was top dog in Boston’s Winter Hill gang. His brother was a Senator for the Commwealth of Massachusetts, and served as Senate President for several years.

It is said that Whitey was an FBI informant, and that his handler, FBI Special Agent John Connolly, tipped Whitey off that he was about to be indicted on racketeering charges. No problem. Whitey had left stashes of cash in safe deposit boxes all around the world, in preparation for the day he had to go on the lam. So he took off in 1995, and the FBI has not been able to catch up. Special Agent Connolly is pulling a ten year vacation in the stir.

I remember when Whitey disappeared, and ever since then, I’ve used him almost annually in lecture material describing the Trivers-Willard hypothesis. It goes like this:

Thumbnail image for 0470656662.jpgThis may or may not be a recent photograph of Robert Trivers, of the Trivers-Willard Hypothesis. The Trivers-Willard model (I prefer to call it a “model” rather than a “hypothesis” because it is not specific enough to really be a hypothesis … it’s a model that generates lots of hypotheses) states that selection should favor the ability to differentially bias investment in offspring by sex if the two sexes have differential variances in reproductive success, and if there is any way to predict offspring rank. That’s a bit thick, so it requires some examples and further explanation. Maybe a story about a mobster would help..

OK, so an example: Red deer (also known as Elk) give birth to one offspring (max) per year. Males compete for access to or to be chosen by females. So, only a small percentage of male red deer mate in a given year, a significant percentage may never mate at all, and a very small percentage sire many many little red deer. Male red deer have a high variance in reproductive success. If you tried to predict how many offspring a given randomly chosen male would have, knowing nothing at all, your best guess would be the average number of offspring red deer have in an average lifetime. But you would be wrong almost every time because the actual number is highly variable. Male red deer have high variance in RS.

Females, on the other hand, have a pretty standard number of offspring. There is not much competition among them, they can always find a male to mate with, etc. If you needed to guess how many offspring a particular randomly chosen female red deer would have in a life time, you could guess the average, and you would be right on or very close. Female red deer have low variance in RS.

So, male and female red deer have differential variance in RS. Males high, females low.

If a female red deer could somehow “predict” the likelihood of her offspring getting to mate, i.e., if she could tell if any offspring she had in the present year (male or female) would be average vs. high ranking, then selection should favor the evolution of a mechanism to actually give birth to the appropriate sex offspring (thus biasing investment in one sex or the other). It turns out that she can. A female red deer that is herself average or lower-quality (thin, ill, injured) is likely to give birth to an offspring that will be either low ranking or average. But if the mother-to-be red deer is high ranking, she is likely to give birth to an individual who will grow up to be high ranking.

Under these conditions, she should have a female offspring if she’s average or low ranking, but a male if she’s high ranking. And that, it turns out, is what red deer actually do.

That should be clear. But in case it isn’t, let’s take it down do real life, and bring in the gangsters.

You check the mail this afternoon, and there is a letter from a law firm you have never heard of. It says that your Great Aunt Tillie (whom you’ve also never heard of) just died, and left you with $1,000 in her will. The check is enclosed.

Thumbnail image for 0470656662.jpgThis may or may not be a recent photograph of a male red deer. Holy crap. Found money! What are you going to do with it? So you and your close advisors (your roommates, your cat, etc.) discuss it and you narrow it down to two choices. Choice A and Choice B.

Choice A is to go to your broker and buy $1000 worth of a nice, relatively safe mutual fund. The fund will buy and sell reliable blue chip stocks, thus spreading the risk over several companies, and over time you can expect to get a return of 50 bucks a years, easy.

Choice B is to buy 1000 one dollar lottery tickets. Your chances of winning are slim, but if you do, you will win 87 million dollars.

So, what do you do? The obvious sane choice is to buy the mutual fund.

But what if your cousin is Whitey Bulger? Whitey Bulger, as head of the Winter Hill Gang, is said to have owned the director of the Commonwealth Lottery agency.The connection between Whitey Bulger and the Lottery has never been proven. They don’t have a shred of evidence. He was, however, indicted for 21 counts of RICO-Murder. It is said that one of the things that tipped off authorities about this is that some of his relatives were winning the lottery a little more often than they should have. So, say your cousin is Whitey Bulger, and last time you saw him (at a family wedding) he told you … “hey, if you ever want to take a “chance” on the lottery, let me know … I can make that work for you…”

So now, you have two choices.

Choice A: Invest in a mutual fund and gain a return of 50 bucks a year (that’s dollars, not elk); and

Choice B: Buy 1000 PowerBall tickets and have a great deal of certainty of winning 87 million dollars.

What would you do?

In case it isn’t already clear. the baby male elk is a lottery ticket, the baby female elk is a mutual fund, but the female can guess pretty accurately if the lotter ticket (male offspring) will pay off. Because the elk’s cousin is Whitey Bulger. See?

How Do You Get Sexual Orientation and Gender in Humans?

Humans appear to have a great deal of variation in sexual orientation, in what is often referred to as “gender” and in adult behavior generally. When convenient, people will point to “genes” as the “cause” of any particular subset of this diversity (or all of it). When convenient, people will point to “culture” as the “cause” of … whatever. The “real” story is more complicated, less clear, and very interesting. And, starting now, I promise to stop using so many “scare” quotes.

Continue reading How Do You Get Sexual Orientation and Gender in Humans?

Evolutionary Psychology: Careful, some practitioners may be carrying a kitchen knife!

Darwinian Psychology, or really, any “Psychology” that claims to be science, will operate under the assumption that the human brain, as an organ, has arrived at its modern form through the process of evolution, which includes a certain amount of design through Natural Selection. It does not take that much additional sophistication to realize that the human brain is not only good at, but absolutely requires for typical functioning, a great deal of learning. Therefore, it is reasonable to assume that the typical human brain functions as it does because of information provided by the genes that were shaped by evolutionary forces and information provided via learning, from some combination of culture and personal experience, which by the way, could also be subject to Darwinian selection (and includes the behaviors generated by other human brains, which in turn, were subject to Darwinian selection).

A simplified model for the development of typical behavior in humans might include these elements:

1) Behavior that emerges no matter what because genes make that happen. If you want to go see some of that, sneak up behind a friend and poke them with a sharp object. They will let out a primal sound and jump. They didn’t need to learn that.

2) Behavior that would not be observed at all were it not for enculturation or learning in the individual. If you want to see some of that, check out the languages people speak. Regardless of how language itself emerges in individuals, one is not genetically programmed just to speak French. One learns one’s language, and the language one uses is a very important behavior.

3) Behavior that is only “normal” (normative in antro-speak) or “typical” when it develops as a combination of those two things (canalized learning). This is a bit harder to explore. Looking at language in a different way than above might be one. Another might be looking at individuals with an upbringing that deprived them of the usual cultural inputs, like some of the classic “wild child” examples.

(I’m avoiding defining what “behavior” is to allow this discussion to fit into one blog post!)

This is basic Evolutionary Biology. A lot of people think that what I just described is Evolutionary Psychology. If it is, then Evolutionary Psychology has broadened its mission considerably, which would be fine. But Evolutionary Psychology is more narrowly defined than this. Specifically, Evolutionary Psychology assumes the existence of “modules” in the brain, mainly in the cerebrum (but there is no reason for them to not involve other brain structures) that are distinct neural systems that allow individual humans to carry out specific behaviors. From Cosmides and Tooby’s Primer on Evolutionary Psychology:

We have all these specialized neural circuits because the same mechanism is rarely capable of solving different adaptive problems. For example, we all have neural circuitry designed to choose nutritious food on the basis of taste and smell – circuitry that governs our food choice. But imagine a woman who used this same neural circuitry to choose a mate. She would choose a strange mate indeed (perhaps a huge chocolate bar?). To solve the adaptive problem of finding the right mate, our choices must be guided by qualitatively different standards than when choosing the right food, or the right habitat. Consequently, the brain must be composed of a large collection of circuits, with different circuits specialized for solving different problems. You can think of each of these specialized circuits as a mini-computer that is dedicated to solving one problem. Such dedicated mini-computers are sometimes called modules. There is, then, a sense in which you can view the brain as a collection of dedicated mini-computers – a collection of modules. There must, of course, be circuits whose design is specialized for integrating the output of all these dedicated mini-computers to produce behavior. So, more precisely, one can view the brain as a collection of dedicated mini-computers whose operations are functionally integrated to produce behavior.

While some of these behaviors might be in some form general to mammals (or primates or vertebrates or some other taxonomic group) they only count as proper modules if they exist in humans as human-specific capacities that are adaptations each shaped by a particular “environment of evolutionary adaptiveness,” altered over time through natural selection, to function a certain way. To be very clear: The functioning of these modules is primarily determined by neural systems that are specified by genes that were, in turn, shaped by natural selection.

The gasp and jump behavior noted above would be a bad example of a “human behavior” for this sort of study because although there are certainly human aspects to it, it is mainly a more general behavior. Try it with your cat and see what happens. A great example from Evolutionary Psychology would be cheater detection. Even if the detection of “cheating” behavior might be found in non-human animals, humans seem to do this in unique human ways. One study that supports and exemplifies this (which I’m a bit familiar with because I helped with it) compared human ability to solve a basic logic problem under different conditions. Briefly, humans were given two different problems, both with the same underlying logic and with the same logically determined answer, but framed in very different contexts. In one setup, the humans were asked to solve the problem in the context of an esoteric filing problem that a file clerk might encounter. In the other context the humans were asked to evaluate the honesty of individuals trying to get a drink at a bar, from the point of view of the bartender. In both cases there would have been an exhaustive, multi-step solution (such as asking everybody for their ID no matter what, or looking in every single file folder to see if everything was filed correctly) but there was also a clear and unambiguous least-step most efficient solution (ask only certain people for their ID, or look in only certain file folders), and the test subjects were asked to provide that efficient solution. In the case of the filing problem, people were shown to be really bad at finding the solution. In the case of the more human problem, where subjects were being asked to asses the chance that people were lying, they did rather well. This suggests that humans have an ability, built into the brain, to handle lying and cheating by other humans. (Here is an example of a recent related study.)

Evolutionary Psychology says that humans evolved to do this during a period of “evolutionary adaptiveness,” living in social groups where detecting cheaters conferred a fitness advantage, or not doing so caused a fitness disadvantage. Moreover, this capacity exists as a brain “module” that develops in individuals by virtue of genetic programming, with the genes doing that developmental programming having been under selection during that period.

An alternative explanation … but still evolutionary and still scientific … might be that the ability to detect cheating emerged in individuals who, over their lifetime, experienced the need to do so and learned, and/or received from their culture through the processes of enculturation, the ability to do so. In this explanation there may well have been gene-level selection to facilitate some sort of data processing or reasoning, and perhaps most importantly, learning, without which individuals would not be very good at developing a cheating detection mechanism.

In both cases, one could say that there is a “mental module” … a neural structure in the brain that is good at doing some thing. In both cases one could say that the module emerged as part of the evolutionary process. Indeed, I regard the result of this and similar experience as very strong evidence that there are modules in human brains that are really good at doing certain things, and that are sufficiently specialized that they are also bad at doing similar but in some sense “unnatural” versions of the same thing. In an Evolutionary Psychology version, the module was mostly built neurologically because of genetically specified development. In a more general Darwinian Psychology, brains are selected (though evolutionary process) to be good at learning how to do this sort of thing.

One way to test this would be to raise a group of babies in a cultural environment in which it was not necessary to ever detect cheaters, but where day to day activities of import required being really good at file clerking. If Evolutionary Psychology is right and Darwinian Psychology is wrong, then the adults that emerge from that experience will test the same way on the previously described experiment (or maybe a little different, but the pattern would be the same). If Darwinian Psychology is right and Evolutionary Psychology is wrong, then when confronted with a test for cheater detection vs file clerking, the test subjects will excel at file clerking and be lousy cheater detectors.

It is possible, of course, that both things happen: there could be genetically determined human-unique modules AND a set of general learning capacities.

ResearchBlogging.orgIn fact, much of the better research in Evolutionary Psychology addresses the potential combination or overlap between these developmentally distinct explanations. A recent paper by Fessler et.al is a great example of this. The paper, “Weapons Make the Man (Larger): Formidability Is Represented as Size and Strength in Humans,” tests the idea that when assessing the degree to which one should regard a foe as formidable, humans narrow down their assessment into a generalized variable that is very likely to have emerged as a cognitive tool during our Old World Primate/Ape ancestry: Size. They conclude “… knowing that a man possesses a gun or a kitchen knife leads people to assess him as larger and more muscular. In conjunction with prior work, our studies thus provide strong preliminary evidence that the conceptual dimensions of size and strength are employed to represent relative formidability.” To me, that is an excellent example of a study of evolved human capacities, done by a team of researchers who call themselves “Evolutionary Psychologists,” which does not ignore, but rather incorporates, the most likely scenario for the evolution of the human mind; human brains are the product of millions of years of evolution and specific human capacities emerge as a conjuncture of innate abilities and drives (attention to “bigness”) and individual culturally mediated experiences (understanding of the artifacts of violence) combined and fine tuned by forces that are worthy of further exploration.

(I would note that the lead author on this study, Dan Fessler, would be one of the first authors I’d point someone to whom might be interested in reading some “good Evolutionary Psychology.”)

“Evolutionary Psychology” can be viewed as distinct form a more general “Darwinian Psychology” which simply says that the brain is shaped by evolutionary forces, or a “Behavioral Biology” that might derive from both human and non-human primate studies, which could assert that typical human behaviors are the result of an unspecified (but knowable) combination of evolved genetically determined capacities or drives, and learning. hese are very different ideas, but many people conflate or confuse them.

Brains evolved. Sometimes, when criticizing Evolutionary Psychology, as I’ve done now and then and as Rebecca Watson recently did, those who call themselves “Evolutionary Psychologist” react in an interesting way. They claim that the criticisms are unscientific. They may label the critics as “creationists” or “science denialists.” I some cases, a defender of the subfield may even resort to cherry picking among the perceived attacker’s prior writings to falsely show that they hold certain beliefs. This sort of reaction has been observed of others who undergo criticism by people who really do hold similar fundamental views, but who do not agree in total with a particular position. I wonder if this reaction is a human universal of some sort. Perhaps, even, a module. It would be interesting to see this developed as a research project.

Fessler, D., Holbrook, C., & Snyder, J. (2012). Weapons Make the Man (Larger): Formidability Is Represented as Size and Strength in Humans PLoS ONE, 7 (4) DOI: 10.1371/journal.pone.0032751

See also:

?EP: The fundamental failure of the evolutionary psychology premise

?EP: The fundamental failure of the evolutionary psychology premise

Is evolutionary psychology worthless?

Reason.tv: Stone Age Minds – A conversation with evolutionary psychologists Leda Cosmides and John Tooby

How Girls Evolved to Shop

Rebecca Watson gave the following talk at Skeptcon. It is funny, well done, and critiques a Pop-Evol-Psy concept or two, which I have also addressed (Why Do Men Hunt and Women Shop?, Understanding Sex Differences in Humans: What do we learn from nature?, Falsehoods: Human Universals, A Tutorial in Human Behavioral Biology, Driving The Patriarchy: Demonic Males, Feminism, and Genetic Determinism, Race, Gender, IQ and Nature, What is the most important human adaptation?, How Do You Get Sexual Orientation and Gender in Humans?, Men = Testosterone Damaged Women!, Sex and Gender in An Odd Primate), as Rebecca notes, thank you Rebecca! I don’t agree with everything Rebecca said about the role of men and women in forager societies, but that isn’t too important to her talk.

The original video is HERE. Please be so kind as to go and “like” it, as there will be many haters who will bother to go and “unlike” it because they are haters.

CLICK HERE for my followup post on this. And, HERE is another, related post.

Marriage

I am going to write a bunch of blog posts about marriage.

You should regard my opinion about marriage to be valuable; I’ve had several of them. And in this way, I may be more like a hunter-gatherer than a “modern” Westerner, as the practice among the former is to treat marriage as very important and each partner in the marriage as a critical and similarly empowered member of the contract, while the practice among the latter has been to see women as the man’s property and to form economic, social, and sexual alliances as needed outside the marriage. Who is in on the deal and how they work together to get the job done matters.

As we approach a very important election in the United States, the issue of marriage…what it is and who decides how to do it…looms large as a political issue. People who are of the same sex want to get married, and about half of everybody says no. Why? Why do people of the same sex want to get married, and why does either a slim majority or a bare minority care enough to try to stop this?

One of the things that has been said is that marriage between a man and a woman is what God specified, via his various media outlets. Iron age pamphlets, burning bushes, that sort of thing. That is a religious argument for disallowing people of the same sex to get married, but there is also a secular argument; it ain’t natural. The natural form of marriage is for a man and a woman and nobody else to get married. There are all sorts of interesting questions raised by both arguments, and it is interesting to see where they agree and disagree; almost every person mentioned by name in the old testament who was married whether they were a FOG1 or not was involved in a polygynous union, not a “one man-one woman” marriage. Clearly, the Biblical argument and the Naturalistic argument are at odds.

I really am kind of an expert on marriage, and not only because I’ve had a few. I am an anthropologist and we anthropologists study, among other things, kinship and related social relations. That’s marriage and some other stuff. Also, as a biological anthropologist I’ve had a great interest in the genetical and Darwinian aspects of kinship and marriage. Finally, as a palaeoanthropologist, I’ve studied the origin of marriage. As a matter of fact, I’m the co-author of a peer reviewed paper that explains the origin of marriage in our species, and that paper is in the top ten of all papers ever published in Anthropology’s flagship journal, “Current Anthropology” in terms of numbers of times it has been cited. (This is not to say that all those people who have cited it liked it, of course.)

Marriage isn’t simple. It is about social relationships, economics, child raising, sex, power, and all sorts of other things. It is important enough that The Patriarchy has owned it, in Western Society, for centuries. The politics of marriage will likely shape the nature of politics in general, to a disproportionate degree for a social issue, over the next couple of presidential election cycles, as the politics of abortion and choice have in years past. They are related, as I’ve already suggested–marriage and women’s reproductive activities. Having, or not having, babies is an activity reserved for women, and this worries powerful men. For this reason babies have, in Western tradition, been owned or controlled by men, and marriage is one way in which that ownership is asserted. But I’m getting ahead of my self. Let’s just say that many of the sociopolitical conflicts we are experiencing today can be blamed on that age old problem: The Patriarchy. We’ll get to that too.


1Friend of God

Photo by danny.hammontree