Steve: Thanks for joining us. I’m Steve Hsu.

Corey: I’m Corey Washington. We’re your hosts of Manifold. Today, our guest is Mark Moffett. Mark is a research associate in the Department of Entomology at the National Museum of Natural History Smithsonian Institute. He is also one of E.O. Wilson’s last students. As I’ve talked about in this program, E.O. Wilson is one of my heroes, and from reading your book, Mark, I take it he’s one of yours too, in addition to being your advisor.

Mark: Oh yeah, I bought his book The Social Insects when I was in junior high school for a dollar from the science book club. It was awesome.

Corey: Yeah, that book along with the other two in the trilogy, Sociobiology and On Human Nature, had a really strong influence on me. Hopefully, we can get a chance to talk about those books during our time today. Today we’re discussing your book The Human Swarm, your new book. I’d like to begin by how I first came across your name, and that’s by seeing your photographs, first in the Department of Entomology at Smithsonian and then in National Geographic. My impression initially was that you only did photography, but then I began digging a little more, and I see in addition to The Human Swarm you’ve got a number of other books. So you sort of straddle this line between science and art, that I think is rare these days.

Mark: Yeah Corey, I think that has been really important to me. I’m kind of an antiquarian item, I believe, in the 19th-century idea of thinking across disciplines, of getting people together to talk about things across disciplines as part of the fun. I think artists are experts at conveying emotions, and we need that to get the job done in sciences now. It’s not enough to just convey statistics about species lost. We actually have to make people respond to it, that they would care about it. So it’s really part of the fun in my life, just trying to figure out how to make connections — and do the connections, try things out myself.

Corey: At the beginning of the book, you do something that many people tried to do before, and that is to say what’s special about human beings, what distinguishes us from other animals on the planet. Linguists propose linguistic explanations or theories of what makes us different, for example that we’re the only animal with complex language, that has recursion, the ability to produce indefinitely long and highly structured sentences. Philosophers have said that we’re the only rational animal. Yours is a kind of unusual proposal, and it fits with your self-identification as an explorer. What makes us different in your view?

Mark: Well, we’re all animals. I see us as immersed in nature, so I see us as the same but different in unusual combinations of ways. Language certainly is something that’s unique to us. There are elements of it among animals, but it’s unique to us. Certainly storytelling and immersing everything in stories is part of what we do with language, and that becomes unique with us. But I particularly became interested in the idea of identity and identification — originally with societies, and now we’ve branched out and identify in much more rich ways today, but still primarily I think with our societies — and how that reflects our interactions with people around the world, both for the good and the bad.

Corey: You say that one of the really remarkable things about a person is that they can walk into a coffee shop and not get attacked and torn to pieces.

Mark: Yeah, or run away in terror, or at least want to walk up to each individual and figure out who they are. We can be neutral about others, and that’s something that most other vertebrates can’t do and for some reason had been sort of ignored by other biologists, this different approach we have that allows us to have strangers in our life, which is something a chimpanzee or even a bonobo can’t do. A chimpanzee would go crazy in a coffee shop with chimpanzees it doesn’t know. But we in fact pass in New York here thousands and thousands of strangers every day, and nothing bad happens.

Steve: Mark, can dogs do this?

Mark: Well, dogs have been bred by humans to live in our societies, and they certainly respond to humans in the same kind of way they respond very positively to memberships. Of course, I should back up and say that most animals don’t have societies with memberships. The great majority of species don’t. They get along just fine, either being social at times or not being social at all. Dogs come from a background of membership in societies called packs, and their behavior has altered over time to accommodate humans and each other.

Corey: When I read your comment about being able to walk into a coffee shop, I have to admit that I thought about a few personal experiences I’ve had, which didn’t quite work out all that well. When I was growing up in Massachusetts in the ’70s, my mother had the idea that we should spend a little time in the South. One time we were driving to Mississippi to see my father’s family, and one thing that they underscored to us is that we should not stop in Alabama during that trip. Another time, this is about 25 years ago, I was in Washington state, and we were traveling, a friend and I, to Vancouver. We stopped in an IHOP in Bellingham, Washington — to give you a little more detail, this friend of mine was white, female, and a lesbian — we walked into this IHOP in Bellingham, Washington and the place goes silent. We stood around for a minute or two and realized we probably needed to get out of there. After that, we began to talk about this a little bit, and our discussion was clearly they were uncomfortable at the thought that we were a couple. But I think we asked ourselves, honestly, would they be more upset if we were a couple or if they found out that she was a lesbian? So it’s clear in some cases that humans are not that accepting. You’ve got a long discussion in the book about ingroups and outgroups, and my impression is when you come across a kind of phenomenon in people, you often think about animal analogs, in ways in which we may be behaving like other primates or other animals. What’s your thought about the times when this ability to move into different groups doesn’t work?

Mark: Well, there are a couple different aspects of that. Part of it is regional, and that goes back into our pre-history. Hunter-gatherers mostly lived spread out in small camping groups, but they were still part of a greater society. If you asked them who they were, they would give the name of a group that could be up to a couple of thousand individuals spread over a territory. They felt like one group, they would act as one group when they met their neighbors, but still, at the far end of the territory they wouldn’t necessarily know what was going on. Cultures could change, ways of dressing, lingo, and so forth, and when they got together they might not necessarily be comfortable with each other anymore. Now that we have more communication going on and more efficient ways, our societies have grown in part for that reason bigger, and we can be comfortable with a broader array of people, but there are still regional differences. Going back way in time, those regional differences could lead to societies severing apart, so part of the question is, when people become so uncomfortable that the society will break down and form new societies or usually divisions, in the case of hunter-gatherers, into half. The other aspect of that is that humans are facing something that is truly unique across creatures, in that no animal has an ethnic group in their societies — and early humans didn’t either. So these differences between us are treated in our brain sometimes as if we belong and don’t belong, even if the rules of citizenship say that we do. This kind of stress between how our brains register each other and the rules of the society as a whole can reach a peak in cases of immigration and so forth. This is a dissonance in our society that we’re facing all the time, particularly in times of stress.

Corey: You have a pretty interesting discussion in your book about immigration, and I want to get to that in a little bit. First, I want to talk about your Wall Street Journal op ed. That came out a couple weeks ago — we’ll have a link to that on the show page — and there you emphasized the importance of markers for group identity and how important those are. I guess the idea is, to basically fit into a society, you’ve got to signal that you are part of that society, and that applies even to humans.

Mark: Yeah, this is what distinguishes us from a lot of other vertebrate animals and something that really had not been emphasized before in biology. The chimpanzee is not comfortable with strangers because a chimpanzee literally has to know as individuals every member of its society. That limits its society membership to rather few individuals. There’s presumably some limitations in cognitive ability to keep track of everyone, so these vertebrate animals, including chimps, have societies of a few dozen up to a couple hundred individuals. But humans, once you use a marker, once you use some kind of cue so that you can glance and not even take someone in fully — individuate them, as psychologists would say — once you have those kinds of cues, you can be comfortable around more and more people. Those are the identifying traits that you need to know at least that they belong, that you have certain expectations of how people are going to behave. That’s one of the driving forces that allowed us — it seems very simple — but it allowed us to eventually form large societies. It’s been really overlooked by biologists. It’s more of an issue that is confronting psychologists as they look at identities in ingroups and outgroups.

Corey: You see this as playing out in current politics, as far as I can understand. In the debate over immigration, you bring up the fact that it’s pretty important for people who want to come to this country, or any country, to begin to look and act like they do. Is this something you think that people are aware of, or is it something that they learn over time? Is it something you think that might actually begin to ease the difficulty of someone coming to assimilate in the US, say?

Mark: Well, there have been a lot of options across human societies, but basically the reasons that ethnicities don’t occur in other species is that societies don’t freely merge. When you look across species, once a society is formed, they stay apart. So the fact that we have all these different groups living together in a society now is an indication that something different has happened. You don’t find that kind of group in early hunter-gatherers. You don’t find ethnic groups, races in early hunter-gatherers. The early hunter-gatherers could take in refugees, they could take in mates from other societies, and It was that capacity that I think was the starting point for our ability to take in larger proportions of other groups from neighboring societies and cultures. The people coming in, a mate coming in would be expected to learn the language and some of the identifying traits, some of the things that were more important to the people there, but such a person would never be able to take all of them in. He or she would still probably have an accent, probably still not know how to dress correctly or have the gestures down of the local people and so forth. The differences would remain. This balance between being the same and different has resulted today with immigration in all kinds of variations within societies, which leads to this mental confusion sometimes about who truly belongs and who doesn’t. The awkward thing about being an American is, if you ask someone to picture an American, whatever the race is, they’re going to picture, as it turns out, a white male person. This kind of identity difference, and particularly the importance of the dominant ethnic group, has played out throughout history.

Corey: I want to zoom back a little bit, because I think your perspective is pretty unusual. When you talk to a historian, they are constantly noticing antecedents to events that happened at a certain point in time — not the idea that history repeats itself, but often there are variations on a theme. When you begin to look at events in human behavior, how do you begin to analyze? Do you begin to look for similarities with other animals? I just want to sort of get your thought process, try to understand how you’d approach something that you see as an unusual phenomenon for humans.

Mark: Well, let’s see. I started off thinking about animals and found myself being drawn more and more into what is now being discovered in psychology. I’m very fortunate to have had large sections of the book read in advance by some of the leading psychologists like Roy Baumeister, Marilynn Brewer… There were a bunch of psychologists that really put their mark on how I was thinking about these things. I don’t think of myself as being distinct from any particular group of scholars in this. It was more of, for me, managing perspectives from different fields and trying to get people hopefully to read the book no matter what field they’re coming from. Of course my mentor, E.O. Wilson, Ed Wilson, was attacked for bringing biology into the social sciences, but I think it’s just as valuable to bring the social sciences into biology, and in part that’s what I’ve done. I’ve introduced a lot more psychology than biologists are used to thinking about.

Steve: Mark, would you characterize yourself as an evo-psych person?

Mark: I suppose yes. The trick is, for writing this book, I really didn’t want to worry too much about some of the issues that are considered central in that point of view. There’s a lot of discussion of group selection and evolutionary pressures and so forth. I actually avoid getting too deep into the evolutionary arguments. I think in fact I’m worn out by them. There have been lots and lots of books on them. I’m more trying to express what I see as the structure of societies. If people want to take that within their own discipline, for example evolutionary biologists, to look at the origins of these things and how they would have genetically evolved, that’s up to them. In fact, part of the pleasure was looking at some of the variations between societies purely from the point of view of practical merits. A lot of things that are parallels between ants and humans have nothing to do with intelligence. There’s no reason to be insulted by the fact that ants are in fact more like modern humans than are chimpanzees. No chimpanzee has to worry about highways and infrastructure, division of labor, assembly lines, complex teamwork, agriculture… All these kinds of things that ants are doing reflect not the intelligence of ants or the fact that they’re genetically programmed more than we are, but more importantly, the fact that they can live in very large societies. Unlike chimpanzees and some of these species that have to actually know each other, ants don’t, and so like us, they can have societies of tens of thousands, millions, and sometimes billions. Once you have that, you have to deal with public safety and health issues. I don’t know if you’ve visited chimpanzees in the wild, but they’re not really into sanitation and public health. Ants have to be. Ants with large societies have sanitation squads full time at work.

Steve: But let me ask, you believe that the complex behaviors of ants are under genetic control? They’re not cultural evolutions that are outside of genetic control?

Mark: Well, it’s not true to say that ants entirely have their culture under genetic control, or that humans don’t. Ants in fact do have a fair amount of learning. We’re finding more and more about that. There’s a lot of individuality among ants. There can be hardworking ants and lazy ants. There can be ants that get to know a certain part of the territory and get very efficient at harvesting in it. There can be ants, for example leafcutter ants, that get efficient at chopping up certain species of trees and seek them out. There are all these individual variations that require learning, but they’re certainly more limited in ants.

Steve: So your primary interest is not whether these complex behaviors, for example like pro-sociality or openness to strangers, are under genetic control. It’s just whether a particular species or civilization has it or not.

Mark: Exactly. I think it’s important to sort of lay the groundwork of what we do now. For a book like mine, of course, I’m covering so much ground that there’s going be a lot of holes and gaps and so forth. I’m trying to fill them in, and maintaining a certain perspective on them that’s my own as well. These kinds of arguments go down this path where we’re suddenly just talking about whether warfare is genetic or not, which I find [has] been going on for too long. It’s more interesting to figure out when things like [unintelligible] warfare occur, under what circumstances, and let the theoreticians worry about the genetics and probably come up with great ideas. It’s just not the way my brain works.

Corey: Let’s talk about warfare a little bit because it’s sort of a significant part of your book. You’ve got this interesting term, dechimpanzeeization.

Mark: That’s actually I think Jane Goodall’s term originally.

Corey: Okay. That’s analogous to the term dehumanization for people that often occurs when you have war.

Mark: Yeah, it occurs all over the place. We can dehumanize or infrahumanize, which means see people as a lower level of human. It turns out, psychologists are finding we do that all the time. We work past it. Our conscious brains overcome these little biases we have, but they tend to be there unfortunately. One of the real issues of the book is how new societies form, and I argue that that is a discipline that’s been totally overlooked. Societies do break up and form new societies over time across species. That happens in different ways. It’s a matter of turning the familiar into the foreign as the way I look at it, and how that happens depends on the species. The dechimpanization, or however you pronounce it, that Jane Goodall I think originally described, came about because of the horror she experienced when her chimps, which she saw originally as part of one just continuous community, suddenly turned friend into enemy and two societies split off of one. Then she recognized that chimps did have territorial limits and society borders and memberships. That wasn’t clear to her before then, it had been hypothesized by Japanese researchers. In any case, what was horrifying to her is that this moment when the familiar, the chimpanzees that were part of the society, turned into the foreign, suddenly it turned into this blood bath over the next four years. There were continuous deaths of one group by another, including by individuals who had been best friends. This psychological transformation, which you can see in the breakdown of human societies as well, is something I think we need to know a lot more about.

Corey: Did anything drive this division of this chimp society into two groups that Goodall could identify?

Mark: Well, it turns out chimpanzees and bonobos or other close relative species have society divisions very infrequently, and it turns out that’s probably true of most vertebrate animals. In the case of chimps it’s probably once every several centuries, judging by genetic information. So divisions have been seen very seldom — originally by Jane Goodall, and now within the last few weeks by John Mitani in Uganda, a second division of chimpanzees. His information is going to be much more thorough because he was expecting it. He has a lot more field researchers, assistants and so forth. What seemed to be driving her situation was she was feeding the chimpanzees bananas to get them to come where she could observe them. They started competing over those bananas, and that seemed to drive these two groups apart. The groups were there originally though. Part of the process, when you look at this and study it across species and particularly in primates, for example, is that there’s originally some kind of subdivision, some cultural subdivision in humans you might describe or regional group, and those can be there for generations. The chimpanzees had them for years and years, and only at one dramatic turn they separated and formed these two distinct groups. What happens at that moment is unclear. As I say, the competition involving bananas might have been important for her. In Uganda, John Mitani’s group has been separated into two subgroups for many, many years and just split in half, and he is still trying to figure out what happened to cause that final severing.

Corey: Is it thought that Goodall may have actually caused this division through her own actions?

Mark: It could be that she pushed it along very well, but as they say, the subdivisions were already there. Data analyzed recently from her studies have shown that they were there all along, so most likely they eventually would have split apart. That’s shown by the fact that these subgroups form in other primates and eventually split apart. Her society, community they call them, wasn’t that big. It certainly could have grown more. It could be that population pressure is usually the instigator of these things. But in her case, simply producing a competition over food may have set the whole thing off early.

Corey: One of your theories is that we tolerate foreigners much more easily when resources are plentiful. You have examples of this with wolves and other hunter-gatherer societies. First of all, I’d like to get your more expansive thoughts on that, but I also want to understand whether you think that these sorts of divisions tend to happen when you find competition over resources.

Mark: Well, societies in general among animals seem to be based on joining these groups based on some kind of personal gain by the members. You can look at group-level evolution as well. But in general, it seems to be that societies tend to be pretty intolerant of each other across most species. When they are tolerant of each other, it’s usually in species where there’s little resource competition, like bonobos are believed not to have much in the way to fight for when it comes to their food and so forth. So the question becomes how to overcome that, whether that is inevitable or not. I don’t think it is, but it becomes strategically much trickier when there are few resources around, given that one society can potentially grab more than the other. Right away, you have conflict.

Corey: One of the experiences I had living in the states, living on both coasts, was a big difference in how well integrated the West Coast in the US was compared to the East Coast. The East Coast in many ways seems very balkanized to me. You have ethnic groups living nearby each other, but much more segregated. There are pretty severe lines often in New York City or in other cities, and that was much less true on the West Coast of the US. I’d always thought that human behaviorism is in some ways somewhere between bonobos and chimps, as far as our tolerance for others and our willingness to have conflict. It seems like there’s a fair amount of variation in humans for this kind of tolerance. Do you find that ever in other species?

Mark: Well, as I say, other species don’t have ethnic groups, so the sorts of problems we have within societies are rather unique. I mean, we get a lot of gain in terms of creative potential from having all these groups together. We manage to put up with each other and even get lots of friendships going despite these separations into groups, which our minds do automatically and very fast. We recognize groups all the time as we’re moving around the world, including entering a coffee shop, but at least we have the potential for all kinds of possible interactions. I can’t really lay claim to knowing why certain societies end up parsing their populations in different ways. Certainly I think you’re right, the West Coast to me, the comfort with people standing in the bank line or wherever you were, just seems very comfortable. In New York there are more segregated neighborhoods. That isn’t necessarily a bad thing. We like to be around people like ourselves, including personality types, and not just ethnicities but all kinds of similarities to ourselves. Those are choices we make all the time. As long as we’re interacting successfully and well with other groups, it doesn’t seem to matter. Some research suggests that groups get along best when they’re either well separated or well mixed. It’s sort of when things are hazy in between when some more tensions can arise. Studies have looked around the world at that kind of pattern.

Steve: Mark, do you have any specific predictions about human societies and immigration, what’s going to happen in the future?

Mark: I have the prediction that it’s going to be popular and unpopular over time. That’s just always been that way. We are now in a period of feeling threatened for our jobs and resources, and even sometimes for our lives, by outsiders, but hat was true going back in the 1960s, 1910s, 1860s… In fact, Peter Turchin has suggested cycles of 50 years for these kinds of problems and intergenerational thing going on, where we get stuck into this feeling of not being comfortable with others in the room as much as we were before. Immigrants are a primary source of threat in that sense because they are completely foreign. The whole idea of having immigrants come into a society, as far as I can tell, is a relatively modern idea of the last few centuries. There may have been some instances in Rome and earlier, but for the most part, people entered societies because of some kind of coercion and dominance. They weren’t just freely admitted to join in the streets with everyone else from the start, and that’s what immigrants are essentially allowed to do. That’s been part of the strength of our country, but it’s something that rouses our psychologies in ways that we still need to figure out how to control, particularly, as I say, in times of threat or competition.

Corey: Steve, do you have predictions about immigration?

Steve: Well you know, we’re entering an interesting era. I think when Obama was elected, people were very optimistic that we were entering a kind of post-racial America. I thought that was a little bit too optimistic. Mark, I’m curious whether you think we’ll ever reach a kind of completely post-racial society where people look back and say, “Oh yeah, a hundred years ago people were obsessed with these really trivial differences between groups, and how silly that was. Now we’re all past that.” I think the counterargument might be that it’s somewhat hardwired into us, and so even with a very strong cultural evolution in that direction, we’ll never fully lose a kind of ingroup-outgroup preference based on superficial characteristics.

Mark: Yeah, I think we’re going to find those differences no matter what they are. Even if we cross-marry and so forth into the future, we’re still going to pick out groups. Our brains do seem to do it automatically. Even a three-month-old child recognizes others of the ethnicity of its parents and responds more positively to them. In fact, child psychologists, some of them talk of children as being little stereotypical machines, and you basically grow up learning how to cover up those differences and negate them as much as you can. But the trouble is they never go away. Even the most positive liberal person can still make errors. Doctors famously still prescribe drugs mostly to whites in America. Ironically, this may be one of the reasons for the current problem with drugs among poor whites in America, as they’ve been overprescribed compared to blacks. But as I say, what this means is that we show these biases all the time without even recognizing them, even if we try hard. In fact, if we try hard, we tend to bring up biases just because the elephants in the room become even more prominent for us.

Corey: I guess I’m kind of in the middle on this point. I’m a little bit pessimistic about people ever getting completely beyond these things. I think many of them seem very deep in animal cognition, insofar as we’re animals: we share a lot of these tendencies to identify people as similar to us or different from us. But there’s a fair amount of change going on in society. I drop my daughter off at her preschool. Between a third and a half of the kids in her class are interracial, and it’s not clear to me how those kids see the world, because the groups that they now belong to didn’t really exist up until a few years ago. I think it’d be actually an interesting experiment to see someone like my daughter, who’s half African-American, half Bulgarian — I mean, who’s her ingroup? — and if that’s an increasingly common phenomenon in the states. I remember when I was in Stanford 30 years ago, the largest “ethnic” group there, minority group, was actually interracial kids, and that was California in the mid-’80s. You’re finding something actually very similar in East Lansing in the 2010s right now, and I actually wonder how these phenomena are going to apply to kids like that.

Mark: That’s a really good question. It depends on their ethnic mix and other things, in a large part, we don’t know. For groups that have had a history of being mistreated like the blacks, this one-drop rule remains in our heads, in which we receive a person as black even if they have a tiny proportion of African genes in them. But the more important thing here — and I think the one you’re thinking of Corey — is the fact that we can override these things, and I think we are moving in that direction. These groups are always going to be with us. Our memberships are important to us, they give us a sense of meaning and validation. They include not only ethnic foods and cuisines and other things we like because we belong to a particular group, and we’re not going to lose those, they’re going to be important to us. It’s a question of how we treat each other, and particularly how we respond to the emergence of differences — regional differences, local differences, whatever they are — because in the past, differences that have arisen have led to the breakdown of societies. The question is, do you squelch these differences? That doesn’t seem to be possible. As differences emerge, as cultures change, there’s going to become points when people don’t feel like they belong with each other anymore. That’s a very big problem in the long term, in terms of thinking of societies at least.

Steve: Mark, we had a guest on some time ago who is a, shall we say, adherent to the philosophy of the Unabomber. He’s very anti-technology and anti-modern society. I think very central to his world view is the idea that we evolved primarily as hunter-gatherers, and therefore modern society, living in these dense urban settings, is actually quite bad for us and prevents us from thriving. I’m curious whether you find his thesis plausible or not.

Mark: Well, it certainly is a novelty for us. It’s a relatively recent thing. It is based a lot more than I’d like on dominance differences — differences in status between people and so forth — that weren’t present in hunter-gatherer societies. Hunter-gatherer societies are often looked down on as sort of childlike and infantile things, but they were based on forms of interaction that seem very foreign to us but are still built in our brains. We’re still capable of them. Hunter-gatherers were very egalitarian, everyone was equal. Women had a big say in things. They also were really into sharing — in fact, a successful hunter often didn’t eat any of his meat, he gave it to everybody else. And this is true around the world: these are universal patterns, it appears, for people living in these what we call band societies. So heck, I wouldn’t have minded being in such a society, it seems pretty good to me. In fact, they didn’t have to work much. You only needed to do a certain amount of work today and you had a lot of time for conversation and gossip. They weren’t into materialism. Maybe if you’re into materialism, you’ll want to be in a modern society. Maybe if you’re wealthy and you’ve got power, you certainly will want to be in a modern society, because hunter-gatherers didn’t put up with it. So as a person, I guess you’d have to decide what you want. [laughs] But our societies do seem to function today, and it’s pretty amazing that they do. I would say that’s because we’ve had these attributes, including this allowance for differences in power, prestige, wealth, materialism, and so forth, even as early human beings. These traits would come up in situations that were useful at the time, or functional for that society. I think we’ve always had this full range of possibilities, and we just now express it at a larger population than we did before — at least some of those possibilities. The less fair wins, unfortunately.

Steve: I think your characterization of hunter-gatherer life is similar to our previous guest. That’s part of the reason why he thought modern society was extremely bad for us, having hierarchies and inequality; but also I think for him it was a big deal that you would spend a lot of time around strangers, actually — that it would be better to live in a small community where most of the time you saw people that you were very close to.

Mark: Well, that’s certainly true. That is a difference, but only to a degree. What I point out in the book that is important to remember is that we always did live with the capacity to be around strangers. Even these early hunter-gatherers, as I said, were spread out over space. They couldn’t all live together because the game animals they hunted didn’t allow it. They had to be out in small camps hunting in smaller groups, and they didn’t necessarily know the people at the far end of the range. There are indications throughout the literature that even when societies were a couple thousand individuals — Cory Apicella, one person today studying a group of hunter-gatherers, says they don’t even know the hunter-gatherers in their society at the far end of their territory, even though there are a couple thousand of them — so this capacity to be around strangers and comfortable with them is, I think, a universal human trait. Certainly now we are overwhelmed with them, and yet we’re more comfortable with them than we like to admit. You were saying, Corey, that you can go to parts of the country or be in an ethnic group where things aren’t quite comfortable for you, and things won’t necessarily always be easy in that coffee shop. But in fact, it’s amazing how readily we deal with others — including foreigners — nowadays. Our capacity to live in this existence is really extraordinary and still needs to be explored. Our identities are now really complicated in the ways that hunter-gatherers never imagined, and that leads to a great richness in our lives as well. So I wouldn’t deny people the right to say that modern societies are superior, or that hunter-gatherers societies are superior, because that’s up to their perspective I guess.

Steve: I think earlier you were saying you’re a little bit atheoretical about these things. But why is it that humans are more open to strangers and cooperation? Is it just a consequence? I think you’re saying it’s not just a consequence of our general intelligence because, for example, ants have that capability I guess — although I guess in the ant case, they’re all closely related to each other. What is your explanation for how it arose between chimpanzees and ourselves?

Mark: Well that’s really interesting, because in fact these markers, as I call them, these little cues or signals that tell us who belongs and who doesn’t belong, are very low cost and don’t require any commitment from us. You can simply have a password saying that “I am part of the group” as you enter your group. Some birds potentially have that, and I would say that’s likely the case originally for humans. You would simply have some way of identifying yourself as part of the group. Whether you’re known or not is almost independent of that, because you can be a known person and mistaken. But if you’re on a basketball team where everyone’s wearing the red shirt, you don’t have to know that that’s Joe. You just throw the ball at the guy with the red shirt because he’s part of your team. These cues really simplify how much we have to expend in our brains all the time. They make life cognitively easy for us. There’s no reason for those kinds of things to happen way back in history. In fact, chimpanzees have something that approaches that. They don’t have a red t-shirt to indicate who belongs to their society. They have these cultural differences, but they don’t use them to identify who belongs. A chimpanzee that cracks a nut with a rock in one community and they don’t do it in the next community, if somebody doesn’t know how to crack a nut with a rock, they don’t attack them. These aren’t used to indicate who belongs and who doesn’t. But they have one thing that might be used that way, and that’s called the pant-hoot. It’s the sound that Jane Goodall makes when she’s trying to impress an audience. This hoot, this marvelous noise, carries for miles, and within each community they come up with their own hoot. They copy each other. They don’t appear to use it to indicate that “I’m part of your group, don’t worry about me.” They use it to tell who belongs from a distance. They can hear off in the distance that it’s a pant-hoot from our group there, a pant-hoot from foreigners here. You can imagine a very simple change where you start using that in a regular way around other individuals to indicate their membership. There is one story about that if I may. That’s a story of Andrew Marshall at the University of Michigan. He was studying a group of captive chimpanzees on an island down south in the US. They had a pant-hoot they had all agreed on, but one male in that group was incapable of pronouncing it correctly. He couldn’t get the accent right, and they wouldn’t let him feed. They eventually drove him into the moat and he drowned. So there is an indication of what might well be the use of a signal by a chimpanzee to indicate “I belong” or “I don’t,” even an individual that’s well known in that case.

Corey: We’re coming towards the end of our hour. I’d like to get a sense of where you think this kind of synthetic approach to understanding human behavior, animal behavior has come in the past 40 years and where it’s continuing. Forty years ago, Wilson wrote On Human Nature. It really was up for grabs whether human behavior was under genetic control or it was learned. I think he convinced a fair number of people that we do have deep commonalities with other animals, and that a large part of it is under genetic control. My impression is you take a lot of that for granted. Where do you see this type of synthetic research going in the future? Because a lot of research has become increasingly specialized, and your work is very, very synthetic.

Mark: Well, the goal of my book, as I think I may have said, is I’m hoping to get people from different disciplines to read this thing, because I actually went to quite a few people across fields to get their opinions on how I should express these things. To me, the big opportunity is that kind of consilience is what Ed Wilson called it, the possibility of bridging fields, because as we increasingly become specialized, we’re becoming less and less likely to solve problems that require knowledge across specializations. My sense of it, as I spoke slightly about before, is that there is a need for a passage of information that goes two ways a lot more. The idea that biology is showing us the genetic roots of things is all very well and good, but to figure out problems, we have to bring psychology and sociology into biology, and the same with anthropology: across these different disciplines, we need to figure out how things actually work. You don’t necessarily have to think of things as being genetically determined to get a lot of mileage out of that, so as I say, I’ve kind of been avoiding that to a large degree. There’s an implication that if we’re assessing each other automatically and almost instantaneously that there has to be a genetic basis for it, all well and good. But I’m not interested in that genetic basis for it as much as I am in the implications of the fact that we all see each other that way and put each other in groups that way, what those implications are for the success of people within societies and relationships between societies.

Corey: Let’s talk a little bit about your photography as we close. I’m curious, when you go into new society how do you go about … First of all, do you photograph people? Because I’ve seen your animal photographs, but I don’t think I’ve seen a photograph by you of a person.

Mark: Fortunately for me, I’ve had the opportunity to live with various tribal and hunter-gatherer groups. But just as I can dive and appreciate underwater nature without photographing it because I know there are so much better photographers out there for the underwater realm, I tend to focus on animals on the above ground realm, and take in people and socialize with people as I travel around without photographing them that much. That’s my explanation for it. I do tend to focus on animals, but I’ve also been intrigued everywhere I go about these differences. I remember one situation when I was an undergraduate: I was an assistant to a coleopterist looking for beetles up in the Andes in Peru, and we were driving around 13, 14, 15,000 feet — higher than any of the mountains in the 48 states here — and in the distance you’d see something that looked like a patch of light green, and you get closer and you realize it was a village covered with moss, and everyone in it was wearing a certain costume and had a certain look. You’d drive on, and then hours later you’d come to this next isolated village, and they’d have a different costume and a different look. As a person who grew up in cities in a big country, this was a remarkable thing for me. I started to think about human groups in ways that I might think about animal groups, because I do think this ingroup-outgroup identity that psychologists talk about crosses over to other species in ways that can teach us something about our own.

Corey: Did you ever try to photograph the people you met?

Mark: I’ve had a few photographs of the people I met. I’ve photographed Machiguenga Indians at what’s called a devil’s garden in Peru, and tribal people eating tarantulas — they’re delicious by the way — in Venezuela and so forth. But the photography wasn’t the main thing for me. I’m only interested in photography if I have a particular story to tell. Otherwise I don’t even want to pick up a camera. Do you know how heavy and annoying cameras are? Cellphones have made things so much easier. When you get back to those old-fashioned cameras and all those piles of gear… if I have a story, I get all excited about it and I’ll pull out that gear.

Steve: Mark, before we run out of time completely, I wanted to ask you a little bit about E.O. Wilson. When you were his student was he still involved in the sociobiology controversy, or had that all passed?

Mark: No, he was still working on issues. He was working with a guy named Charles Lumsden, now up in Canada, a person trained in physics. They wrote books about genes, mind, and culture and showing the connections between them, so this was still a big part of his life. He’s shifted over certainly more to conservation today, that’s clear, but at that time he was balancing between different fields as he’s always done, including doing lots of work on ants, on humans, and conservation when I was his student.

Corey: Did Wilson ever talk to you about what it was like going through the difficulties he had to endure early on with sociobiology?

Mark: Well only peripherally, I guess I’d say. Wilson is an optimist to a degree that’s always astonishing to me. Everything is going to turn out, he’s moving forward, all is good and making sense. So he would look back on those things as difficulties he went through in terms of this positive outlook of building this subject and his success. Of course, in the end his positive outlook I think won, because in general, sociobiology — though it’s been rebranded again and again — has entered the popular consciousness to a surprising degree now. Our ability to think about biology and so forth has opened up whole new worlds for people like me to start exploring ideas.

Corey: Steve, do you have any other questions?

Steve: No — well actually, so you were in Harvard in the late ’80s, is that right, mid to late ’80s?

Mark: Yes. My wife says I should wear a medical band because I never know what year it is, but I started there sort of like the early ’80s, and then into the early ’90s because I was the curator of the ants there, yes.

Steve: And did you ever interact with Stephen Gould?

Mark: Oh yes, I did interact with Stephen Gould.

Steve: So how did he get along with your advisor?

Mark: Well, of course theoretically not well, but I saw them together once or twice, seeming to have a good conversation, so I would guess in pure strategic terms, they all sold a lot of books through their controversy, [Steve laughs] and it was probably good for both their careers. But Ed is not someone to say anything negative about anyone. He’s done it once or twice, but it’s been unusual for him. He keeps that optimism going. They seemed to get along in those moments I saw them together pretty well.

Steve: There was just an interview I think with Wilson in The Chronicle of Higher Education. He’s quite old, right? He’s maybe close to 100 years old, or 90s at least.

Mark: Oh, 90.

Steve: Ninety, okay.

Mark: Yeah.

Steve: But still I guess pretty vigorous.

Mark: Oh he is. I was at his 80th birthday, and it only seems like three years ago I was at his 80th birthday party. In fact, I was at three of his 80th birthday parties. It was actually embarrassing. The first one was at Lincoln Center and Yo-Yo Ma was playing. I was sitting next to Alan Alda, and Susan Sarandon was a couple down and all this sort of stuff. And I’m going, my goodness, this is a guy that’s not really into movies and popular culture as much as some folks, and yet he seemed to be enjoying himself quite a bit. Then I was at a party for him — and this is again an 80th birthday party — with his graduate students, and that seemed like the real thing. I almost didn’t want to show up at the third party I heard about, because it just seemed like I would be even seen as a groupie, as a graduate student, to show up at three [Steve laughs] E.O. Wilson 80th birthday parties. But I did at least poke my head in. It was at the Explorers Club. I walked upstairs, looked around, and he was sitting next to Harrison Ford and Oliver Sacks on the other side, and he was having a grand old time. It’s amazing how he’s become a public figure. Certainly today that’s important, given his message on conservation, which is now his central theme.

Corey: Well thanks, Mark. I really enjoyed this conversation, and I think I speak for my co-host Steve. It’s been really illuminating, and I hope at some point you’ll be able to come back on the show.

Mark: Hey Corey, I appreciate it. Thanks Steve also. It’s been great.

Steve: Thanks a lot for your time, Mark.