Tag Archives: Behavioral Biology

Understanding Sex Differences in Humans: What do we learn from nature?

Nature is a potential source of guidance for our behavior, morals, ethics, and other more mundane decisions such as how to build an airplane and what to eat for breakfast. When it comes to airplanes, you’d better be a servant to the rules of nature or the airplane will go splat. When it comes to breakfast, it has been shown that knowing about our evolutionary history can at times be a more efficacious guide to good nutrition than the research employed by the FDA, but you can live without this approach. Nature works when it comes to behavior too, but there are consequences. You probably would not like the consequences.

The question at hand is this: Should men and women be given fundamentally different rights? Would it be OK if men and women had different pay for the same job, or different access to jobs? Would it be OK if men and women were treated differently by the law in a way that accounted for the behavioral differences between them that arise from their biology which, in turn, may be partly a function of their evolutionary history? Should men and women have different status because of their gender? Similar questions can be extended to people that are biologically different in other ways, such as by age, gender orientation, physical handicap or, should it be proven a valid categorization, race. But for now, let’s stick with the basic adult male vs. female difference.

Continue reading Understanding Sex Differences in Humans: What do we learn from nature?

Sex and Gender in An Odd Primate

The Gender vs. Sex question…referring to the meaning of those two terms in relation to each other…is standard material for discussion in Anthropology and related fields, but is often left unattended to in day to day discourse. Both terms have internal complexity, with Gender meaning something about people’s identity as well as being a linguistic term, different but overlapping, and of course, Sex is a verby noun sometimes. But when we say “Gender vs. Sex” we are clearly talking about biological things such as chromosomes and genitalia, behavioral things such as attraction and orientation, self image, and so on, as well as the interaction among these things for a given person and for a given person’s interaction in the social matrix. Broadly speaking, “sex” is thought of as biological, “gender” as behavioral, however the last few decades of research and sociocultural maturation of our view of sex, gender and people have complexified this considerably, and the simple versions of these terms are inadequate and earlier, even “postmodern” feminist constructs tend to break easily. For instance, what sex is a person with a female-looking body, a vagina, breasts, all that stuff? Female, right? But what if the person has complete androgen insensitivity? This individual has testes. Wouldn’t that make them male? Such a situation, which is not particularly uncommon, does not mean that we can’t conceptualize complexity, it just means that the term “biological sex” is a bit limited. Continue reading Sex and Gender in An Odd Primate

Your chance of getting pregnant if raped…

… goes down, compared to other forms of insemination, because “the female body has ways to shut that down.” That’s according to Missouri Congressman Todd Akin. But this only works, according to him, if the rape is “legitimate.” From this we can easily develop a sort of Witch Hunt method to determine if a woman accusing a man of rape was actually, “legitimately” raped or if she’s faking it. If she becomes pregnant from the rape, the rape did not happen.

Is this clear?

OK, now that we have that straight, allow me to bring out this one piece of data I thought I’d never have use of. It is a very limited piece of data, not very useful for a large number of reasons. The question at hand can be divided into two parts: 1) What is the chance of a given intromissive internally insemnating sexual event leading to a pregnancy in a woman not on birth control of average fecundity? Then, 2) Does this probability go down, as the good Congresman claims, or does it stay the same.

The answer to the first question is that it is not terribly high. We are not a one-copulation=one baby species. It takes a bunch of tangos to turn out a tyke, on average (but statistics is NOT a birth control method!). As to the second question, it turns out that according to certain data it actually goes up. It is reasonable to suggest that the chance of a single copulation leading to pregnancy if that copulation is rape is about double the overall average. Maybe.

This has been discussed by Thornhill and Palmer, authors of the controversial book “A Natural History of Rape: Biological Bases of Sexual Coercion” and subsequent to the storm of debate that arose from that it has been looked at more carefully and a little bit verified (see this).

I can very easily suggest explanations for this and I can also cast more doubt on the studies. First, the doubt. We have no idea what the actual relationship between having sex and having babies is. One would think we would know, but we don’t. Sure, sex leads to babies and all that, but how many sperm, or how many ejaculations, or whatever, does it take before a single sperm is allowed access to the ovum leading to a pregnancy? Scientifically speaking the research needed to answer this question has not been done. There are no controlled studies in which a sufficient sample of subjects across a range of fertilities (and varying in other appropriate factors) repeatedly have sex with everything carefully measured and controlled. Not one study has done this. I don’t expect there to be one any time soon. Our estimates of fecundity are based on reported data, vague estimates, and a lot of thumb sucking. So, when we have a couple of rape-related studies that show a higher pregnancy rate than background, unless it was a lot higher, we would need to take that with a grain of salt.

But if there really is a higher chance of pregnancy resulting from rape, this still may not mean much. There are a number of reasons this could happen, some of which are discussed in the above mentioned book. One very distinct possibility is that rapists are selecting victims somehow, perhaps with their Darwinian wiles, as it were, or perhaps for purely random reasons, who are slightly more fecund than the larger sample from which the baseline statistic is calculated. In any case, the difference is not large.

But, there it is also not lower. The chance of pregnancy from what the Good Congressman calls “legitimate rape” … a term that will surely live in infamy … is not lower. It might be higher. But it is not lower. The man is an ignorant fool. He is wrong.

Here he is being wrong:

Hattip Kent Jones.

Added: Here’s an idea, ask that this dude be relieved of his duties on the House Science and Technology Committee. Which, amazingly, he is on.

Men = Testosterone Damaged Women!

One in three or four women in the United States will have been raped or seriously assaulted sexually by the time they reach a few decades in age. That will have been done by one or more men. Most people who are killed by another person are killed by a man. This is true whether the killing is legal or illegal. Very few people in Western society get through their entire lives without being affected either directly or nearly directly by some sort of violent crime of some kind or another, and that crime was almost always committed by a man. Wars are mostly fought by men, and are typically started by them.

Men fight over women, they fight over resources, they fight over nothing, they fight over everything. Men fight. Women fight too, and men occasionally bite dogs.

In non-Western societies, where it is harder to get statistics, there are societies where men are less violent and less dangerous. There are also societies where men are more violent and more dangerous. When we look at patterns across societies, we see a couple of relationships that are not perfect but that are fairly predictive. When a society relies on one or more resources that can be damaged by unfriendly neighbors, competitors, or enemies, men tend to get organized to defend those resources. To facilitate defense fierceness, fighting ability or other culturally shaped and modified traits may become very important. Some societies have words that are used as labels for men who kill other men and are thus of higher status. A few studies seem to indicate a relationship between a man’s fierceness, even the number of men he has killed “honorably,” and his likelihood of being polygynous and having more children than other men. But again, there are other societies where sharing and caring, rather than fighting and killing, raises one’s status.

It has been understood for years that male and female roles, attitudes, social skills, and so on vary greatly across cultures, so that the women of one culture may well be more “fierce” than the men of another culture. But it has also been observed that within a given culture, there is usually a relationship between men and women whereby the violence, nastiness, fierceness, bellicosity, and all that is greater in men than in women. Culture and biology, and I use the word “and” here only so you will see a familiar phrase (really, I mean biosocial factors) shape this relationship between men and women (and I use the terms “men” and “women” as shortcuts for two easily defined points on an uneven spectrum of -inities and -osities). And part of that relationship involves neural development and hormonal effects that interact with each other as well as external factors.

And no, it does not have to be this way. A culture can purposefully decide to have the differences between men and women attenuated, to have less violence and less difference in bellicosity between men and women. Some subcultures within an otherwise fairly bellicose Western society have done that. Over the last month I’ve been keeping track of how many times I hear (in person) or read in an email or an IM a person say something like “Imma kill that guy” or “I’ll kick his/her ass if he/she does this/that,” and noting the gender of the person who says it. (These are always meant rhetorically; no one paying attention would consider these statements to be actual threats.) On one occasion the person making the remark was a man. On 15 other occasions by my count the person making the remark was a woman. The object of the remark was male about half the time, female about half the time. In my subculture, it would seem that the women are fierce-ish.

The problem with men, as a group, as a type of organism, as a subset of humans, is that at various points along the way on their journey from the female template on which all humans are built biologically, they have been altered in ways that make them dangerous assholes. Even when we try to reduce the male-female difference as a society, men who do not willingly participate in that often end up being fairly nasty, dangerous beasts; they may be rapists, they may be batterers, they may be some other thing. They break our efforts to have an egalitarian peaceful world. In a way, they are broken. They are damaged, if you will. Some of that damage is facilitated by what you may know of as testosterone (a word that stands in for androgens).

But whatever you do, don’t mention this testosterone caused by damage thing because it will upset them.

I did that a while back; I made the remark that men were women damaged by testosterone. That statement was picked up on a video and broadcast across the Internet and people’s reaction to it have caused a Minor Sorting. Most of the negative reaction to it was from the usual suspects, people who already hated me because I am an openly feministic male. Or because someone in their clique told them to hate me. Or whatever. Other people were more thoughtful about it and objected to the statement because it is wrong. Well, that’s good, because it is in a way wrong, because it is an oversimplification. But it was not meant to be a description of the biological and cultural processes associated with the development of individual personality, culture, and society. I am a little surprised that people thought it was such a statement, because it is so obviously a remark designed to poke certain men in the eye. Some have described this remark as punching up. If you like, it could be interpreted that way, but it was really much much simpler than that. It was poking certain men in the eye. Some people said it was wrong because it was bad pedagogy. Actually, a statement like this can be good pedagogy. But what I was really doing was poking certain men in the eye.

One thing that people who have spent way too many electrons talking about this statement of mine don’t understand is the context. This is the third or fourth time I’ve done panels at the event where this statement was made. For a good number of the audience, this would have been about the 20th time they’ve bothered to show up in a room where I’m sitting at the table in front. Some of the people in the room were actually students who knew me even better than that. The panel itself (this panel and all the other panels, for the most part) are moments when an ongoing conversation is suddenly organized and directed more than usual and for 60 minutes is carried out a certain way, then the conversation continues at the table after the panel, at other panels, in hall ways, and for several hours each night in a party room. This is the first year that some of the panels at this event were videoed and widely disseminated on the Internet. If I do these panels next year, I’ll keep that in mind and make sure I do what I always WANT to do but only actually get around to doing a little: Produce a blog post to go with each panel, BEFORE the panel, then produce an update after the panel that reflects what really went on. That I did not do this for the present set of panels is my fault, but I’ll happily excuse myself from doing that because, as I’ve just explained, the SkepchiCON track really is more of a closed, insular, and small group event and conversations like the one that has been making its round on the Internet have not happened before.

I have found the ongoing conversation about “testosterone damaged brains” to be somewhat less than interesting, full of distraction, very often little more than troll fodder and a huge waste of time. I’ve been asked to explain, to apologize, to produce copious documentation to back up may amazing claims. There are, however, only two reactions to my comment that I’m interested in. One: You go “Ouch” and put your hand up to your eye because I just poked you there. Two: You go “heh, that was funny.” All other reactions are really your problem, not mine. Sorry.

The things I say above about culture, society, males, females, etc. is all pretty well established, nothing new. I put together this list of things to read for anyone who wants to get a basic background in the theory and understand some of the classic works. In addition, see the following:

Children of Six Cultures: A Psycho-Cultural Analysis, in collaboration with Richard Longabaugh

Demonic Males: Apes and the Origins of Human Violence

Mean Genes: From Sex to Money to Food Taming Our Primal Instincts

How old does a toddler have to be before it stops trying to kill itself?

This looks like one of those questions that pops up when you start typing a query into a Google Search Box, but it is really a question asked rhetorically by Claudia Sawyer on my facebook status where I made mention of the fact that toddlers will put anything you give them in their mouth (even after that “putting everything in their mouth” phase is over … they still do it enough that you can’t give them knives or sandpaper, believe it or not).

And there actually is an answer to this question and it comes from science. The answer is about five years old, and here’s why: Continue reading How old does a toddler have to be before it stops trying to kill itself?


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

Evolutionary Psychology is Nothing Gnu

Despite tens or hundreds of thousands of years of very strong Natural Selection, wildebeest do not arrive at the Mara River with a genetically determined brain mechanism or module that helps (much) to keep them from being eaten by the crocodiles that live in the river. Most of the wildebeest that try to cross the Mara in the annual migration have never seen a croc, or a river, before in their lives, or have encountered this situation only once. This would be a very good situation in which to evolved such a mechanism.

Where is evolutionary psychology when you really need it?

“…boys are innately better at math and science than girls…”

Sheril Kirshenbaum has a few comments about a piece in Science addressing innate differences between boys and girls in math. I have to say, it may be hard to accept the scientific truth sometimes, but the research really does consistently say the same thing again and again. In this latest study, the science …
Continue reading “…boys are innately better at math and science than girls…”

Coming to terms with the female orgasm

Why is it so hard to understand a commonplace thing like orgasms?

This post was chosen as an Editor's Selection for ResearchBlogging.orgI think I know why science does not understand the female orgasm. It is because science excels when it breaks free of context, history, human complexities and anthropology, but when a topic requires one to grasp context, history, human complexities and anthropology, then science, especially the hard sciences, can fall short. Also, the nature of the female orgasm is a comparative question, but human sexuality is highly (but not entirely) derived; It is difficult to make a sensible graph or table comparing aspects of sexuality across mammals that usefully includes humans. It is not as impossible as making such a graph or table with “language” (which is entirely unique to humans) but still, it is difficult.

ResearchBlogging.orgThere is another problem as well. Female orgasm is actually a lot like male orgasm, and probably serves the same evolutionary role with one small but important difference. But, that one small but important difference, the ejaculation of seminal fluid by males, blinds researchers to any other function of male orgasms. Seminal fluid is distracting. Male ejaculation and female ovulation are rough homologues, but entirely different in their physiology and timing. Were it the case that female ovulation could only happen together with orgasm … well, the human world would be a very different place but at least science would not be fumbling around in search of an answer for this enigma.

Recent research on female orgasm

The reason I bring any of this up is because of a paper1, just published, that makes the claim that the “byproduct” theory of female orgasms is unsupported. So, I’d like to take a moment to explain the byproduct theory, to explain why this paper does not really address it let alone refute it, and then we’ll get back to the question of what female orgasms really are for. The byproduct theory will not survive this discussion.

The byproduct theory originates with the following observations:
Continue reading Coming to terms with the female orgasm

How Do You Get Sexual Orientation and Gender in Humans?

Humans appear to have a reasonable amount of diversity in their sexual orientations, 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 th is 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?

“Monkeys on our backs” by Richard Tokumei will not even make good toilet paper

Richard Tokumei has written a book that is so bad he is ashamed to put his own name on it. “Richard Tokumei” is the pen name of a ‘writer/editor in Southern California [with] degrees in Humanities and Phychology from the University of California Berkeley” and he has produced a book designed to anger everyone who hears of it in order to create needless sensation and thus, sell copies. Which, once people get their hands on, will make rather low quality toilet paper.
Continue reading “Monkeys on our backs” by Richard Tokumei will not even make good toilet paper

Falsehoods: Human Universals

There are human universals. There, I said it. Now give me about a half hour to explain why this is both correct and a Falsehood. But first, some background and definition.
Continue reading Falsehoods: Human Universals

Tears as a human female adaptation to limit rape

ResearchBlogging.orgThis came up a while ago and I assumed the idea would die the usual quick and painless death, but the idea seems to be either so fascinating or so irritating to people (mainly in various blog comment sections) that it still twitches and still has a heartbeat, but only as a result of the repeated flogging it is getting.

Continue reading Tears as a human female adaptation to limit rape

The Kiss

I went out with a friend. We were both between relationships, and we both knew somehow that this was a date though it was never called a date. And we had a perfectly good time: Good food, good conversation, good drinks. She drove.

When it came time to go home, she drove me to my house in my urban neighborhood and parked on the street near my house. As we were saying our good-byes, she enigmatically unhooked her seat belt. I wondered why. Then, I discovered that she wanted the freedom of movement to lean across the console and give me a kiss. It was a good kiss. It was actually a series of good kisses, and it went on for a while.


And suddenly, there was a loud rapping on the window of the car. We stopped kissing and that’s when we noticed that we had steamed up the windows a bit. So I cracked the window on which the rapping had occurred and there was a police man staring in with his flashlight.
Continue reading The Kiss

Miss A and Miss W, Sexual Jealousy, and Julian Assange

Almost Diamonds has two interesting posts on the Julian Assange sexual assault/rape accusation/charges. I want to make a comment on part of the second post, but this may not make a lot of sense to you until you read both of them. They are concise and compelling so you will not regret the time you spend on them:
Continue reading Miss A and Miss W, Sexual Jealousy, and Julian Assange