A Tutorial in Human Behavioral Biology

If you read only one book this holiday season, make it all of the following twenty or so!

But seriously … I’d like to do something today that I’ve been meaning to do, quite literally, for years. I want to run down a selection of readings that would provide any inquisitive person with a solid grounding in Behavioral Biological theory. At the very outset you need to know that this is not about Evolutionary Psychology. Evolutionary Psychology is something different. I’ll explain some other time what the differences are. For now, we are only speaking of fairly traditional Darwinian behavioral theory as applied generally with a focus on sexually reproducing organisms, especially mammals, emphasis on humans and other primates but with lots of birds because they turn out to be important.

I’m not going to give you the science; Here I’m just going to give you the books. In all cases I’ll provide links to the Amazon page, because that has become a sort of default quick and dirty way of recognizing a book (you often get to see a picture). In many cases, however, these books are not available new, so you’ll have to find them in your local library or used book store, or on-line somewhere. There are only a few that, if found used, should be expensive owing to rarity or some other value-enhancing feature. Some have been so widely used in classrooms that they are readily available at used book stores near campuses, if you can find such a beast.

You will notice that most of these books are old. That is because Behavioral Biology reached a point a few years back when two things happened: 1) It had matured to a standard academic discipline so things like anthologies of the hottest new papers or “oh wow” books by key writers in the field were no longer as common and 2) It started to be eclipsed, in trade publication, by Evolutionary Psychology, which is unfortunate.

OK, I said this was about the books and not the science, but I’ll give you a little bit of science as a framework for the literature bomb I’m about to explode.

Darwin’s Natural Selection has genomes evolving due to differential fitness of specific alleles. There is co-evolution among genes, some of which are in the same bodies, some not, some in the same species, some not, so we get Sexual Selection and various other co-evolutionary phenomena.

Behavior happens, and is facilitated in tetrapods and fish and so on by neural systems which have some basic capacities. Neural and sensory systems, information processing systems, etc. can be shaped by Darwinian selection on the genome or by selection (still likely Darwinian more or less) on the behavior itself when said behavior is passed on extra-genetically, as extended phenotype, culture, memes, whatever you want to call it. This applies mainly to mammals, and within mammals, more in primates and within primates, more some apes. So there is parallel evolution in some species between genes and behavior, which are always interacting with each other.

Neural and sensory systems should evolve to enhance fitness. But fitness can be extended beyond alleles of genes, and include, just like co-evolution does, genes in other parts of the genome, others of the species (the other sex, other ages, etc.) and other species. So, things like Kin Selection can emerge whereby individuals act in the interest of their gene-sharing kin, not just themselves. Perhaps there are higher levels of selection as well.

As behavior evolves, Darwinian influences on it are limited. The degree to which genes can determine behavior in a given species is not determined by adaptive design, but rather, by phylogenetic constraints, developmental issues, and yes, to some extent, adaptive design. No matter how cool it would be to have a brain programmed by genes to recognize when another person is telling you a lie, the genetic coding for this behavior does not exist in humans mainly because it did not exist in primordial mammals or other vertebrates, where the basic brain system we have today was first developed by evolutionary processes. No matter how cool it would be to be born able to produce language, we are not born this way because our ancestors were not born this way and our brains do not develop this way. Many, perhaps most, important behavioral features of brainy primates can’t be coded into genes because of the way brains evolved over tens of millions of years. So Natural Selection, Kin Selection and other kinds of selection on behavior work through a variety of proximate means in humans, including fine tuning of things like “drives” or other psychological features that can be somewhat adapted during development as well as the culture we require to be human and a fair amount of reinvention of roughly the same wheel again and again and again.

Foundations of Behavioral Biology

The basics are to be found most efficiently in some excellent textbooks. If you do not know all the in formation provided across most of the chapters of Martin Daly and Margo Wilson’s textoobk Sex, Evolution and Behavior, then you simply need to read that book. Some of it is outdated, but really, where there are studies that have been supplanted by more recent work, those studies are not usually wrong, just classic. Obviously, you would read a book written 20 something years ago as a book … that is not current. But it is basic. This book must be supplemented with the material in Robert Trivers Social Evolution. It was Trivers that took basic stuff like Natural Selection and Kin Selection and made them part of a larger toolkit of behavioral science, and in particular, introduced the all important Parental Investment Theory, which turns out to explain a fair amount of the patterning we see in bird and mammal behavior.

Here, I will pause for a bit more theory. Kin Selection theory explains why bees commit suicide, but worked (in our minds) initially with bees where there was a single queen mothering all the offspring and not too many male drones. But then suicidal and other behaviors was observed in bees without this social pattern, and lots of insects (and mammals) with the same peculiar pattern of genetics that bees and ants have were found to have bee-like patterns of behavior. Co-evolutionary patterns are often found in one or two species, make total sense from a Darwinian point of view, but then the young turks (graduate students usually) find numerous counter examples showing that the predicted patterns don’t hold up. Since I just made a huge statement (above) about patterns, I’d better point out that it may well be that most cases, or at least many cases, do not fit the rules! Does this mean that the rules are invalid, that there is no Natural Selection or Kin Selection, or Parental Investment, etc. etc.? No, usually not. What it usually means that when people discovered, for instance, an explanation for sex bias in Red Deer offspring (high ranked females have male offspring, other females have female offspring) they assumed that this adaptation was so cool that it must occur in all mammals, and then they discovered that it is actually rather rare in primates and may occur in the end in only a few mammalian species, and seemingly not in humans. For instance. But this does not mean that the so-called Trivers-Willard hypotheses (which you will find described in Social Evolution and elsewhere) is wrong. Rather, this subset of parental investment theory is expected to work only under certain circumstances. And this is true of all of these behavioral models.

Think of these evolutionary models as being like currency behaving in a rather straightforward economy, but where that economy is only a subset of a larger economy involving barter, coercion, bribery, some very intense marketing and with con artists everywhere. Under many conditions the money will change hands in predicted patterns, following the rules, but under most conditions, while the expected values and directionality of exchange is a force, it is only one of many forces. And, the system is likely very dynamic. It may turn out that we don’t live in a world where evolutionary stable strategies … co-evolutionary systems that are stable over the long term are maintained because there is no “better” (more fitness enhancing) alternative … are very rare because, in fact, conditions are constantly changing. ESS’s may be rare, but that does not mean that the evolutionary forces and the definition of what is “stable” are non existent. They are just living the life of Sisyphus.

OK, so when you are done with the basics as suggested above, advance your understanding of the genetic and behavioral theories by taking it to the next level. Go ahead and read (or more likely re-read) Dawkins main books on genes: The Selfish Gene and The Extended Phenotype: The Long Reach of the Gene. Check out Matt Ridley’s The Red Queen: Sex and the Evolution of Human Nature to tie it all together. Then, when you’ve done all that, you are ready to move on to the next level of theory.

Advanced Behavioral Biology

I would start the next phase of learning with one of my favorite books, one I’ve used many times in classes: Natural Selection and Social Theory: Selected Papers of Robert Trivers by, as it turns out, Robert Trivers. This volume includes many of the key papers that were behind the literature cited above that you’ve just finished reading, along with interesting introductory material by Trivers, giving context. You will be more than prepared to read the source material, to understand it better than most people will if encountered on its own, and to see its strength’s and shortcomings. Do report back.

You can read Natural Selection and Social Theory: Selected Papers of Robert Trivers either before or after the following two items, which are by the authors of one of the above mentioned textbooks, and which provide excellent empirical studies of human behavioral biology using strict Darwinian approaches. Both of these books may be fairly hard to find: Homicide and The Truth about Cinderella: A Darwinian View of Parental Love by Martin Daly and Margo Wilson.

Proximate Mechanisms: Hormones and Neurons Galore

Now that you’ve got a good exposure to the basic theory and to some empirical species-wide studies (of humans) let’s step back for a moment and look at the biology a bit more closely. First, you have to understand endocrinology and related neurobiology at several levels, and you also need to entertain yourself with some excellent writing. So, read Mel Konner’s The Tangled Wing: Biological Constraints on the Human Spirit followed by Robert Sapolsky’s The Trouble With Testosterone: And Other Essays On The Biology Of The Human Predicament. To put this in the most important context (as it relates to the most important human adaptation) now read Konner’s The Evolution of Childhood: Relationships, Emotion, Mind, or watch the documentary Childhood (at least the first hour of it).

At this point you are ready to explore the human brain, it’s evolution, and the evolution of language. You’ll want to start with Terry Deacon’s The Symbolic Species: The Co-evolution of Language and the Brain and you may or may not want to contrast this with Pinker’s The Language Instinct: How the Mind Creates Language. I have not read Deacon’s Incomplete Nature: How Mind Emerged from Matter, but it is sitting here ready for me to delve into. I suspect it is very good and very relevant at this point in your exploration.

It’s People!!!

Now that you have the basic behavioral biology, the proximate mechanisms related to hormones, development, neural systems, etc. under your belt, and a bit of real life application to human culture and society, it is time to explore the women and the men of the species. You might want to glance first at the infanticide literature. It turns out, despite protestations by Men’s Rights Advocates, that a lot of what happens in human culture and related human evolution has to do with the fact that men are dicks, and male committed infanticide is a big part of that. You’ve already explored that with Daly and Wilson and Cinderella, above. Now have a look at Sexual Coercion in Primates and Humans: An Evolutionary Perspective on Male Aggression Against Females or a selection of the papers therein. Or skip that part and take my word for it.

Either way, your next stop should be with Sarah Hrdy and these two books by her, in order: Mother Nature: Maternal Instincts and How They Shape the Human Species and Mothers and Others: The Evolutionary Origins of Mutual Understanding. Then, on to the boys with Richard Wrangham: Demonic Males: Apes and the Origins of Human Violence. When you are done reading that, you’ll need some Frans DeWaal to calm down: Tree of Origin: What Primate Behavior Can Tell Us about Human Social Evolution.

Culture and Society

And then, finally, the ethnography. Equipped as you now are with the theory, numerous applications, an understanding of evolutionary background (phylogeny), development (ontology), proximate mechanisms, and adaptive models, you are fully Tinbergened-up and ready to go. I suggest the following three volumes put together (or written) by Laura Betzig (one, two, or all three): Human Nature: A Critical Reader, Despotism and Differential Reproduction: A Darwinian View of History, and/or Human Reproductive Behaviour: A Darwinian Perspective. And then, finally, you will be prepared to understand, at a sublime level, the book that pisses more people off than any in this whole field not written by an evolutionary psychologist: Yanomamo РYanomamö (Case Studies in Cultural Anthropology). The current edition, new is way overpriced. Buy any old edition, really. They are in used bookstores everywhere.

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