Spencer Wells is a renowned geneticist and a National Geographic Explorer-in-Residence. He directs the Genographic Project, an initiative to map the genetic history of humanity's diversity. He has written a number of books including "Pandora's Seed: The Unforeseen Cost of Civilization" and also wrote and presented the documentary film accompanying his book, Journey of Man.
What inspired you to write Pandora's Seed in the first place?
It developed... over the course of many years. It kind of came out of Journey of Man and some questions I had about why we had developed agriculture in the first place. I'd read these interesting statistics, including the Lawrence Angel study about skeletal material from the Middle East, and also about the fact that people seemed to be sicker and dying younger after agriculture came along. I thought that was curious and kind of counterintuitive because agriculture, which was so successful, surely must have made life better for us, and in fact, it didn't. And then also living with hunter-gatherers on several occasions, particularly the Hadzabe living in Eastern Africa... and seeing how these people, who seem to have nothing, seem to be so happy in so many ways and fulfilled even though their lives actually were in danger of being destroyed and all these people wanted to come in and take their land. When they were actually allowed to do their own thing, so to speak, they just seem remarkably happy with virtually nothing in their lives compared to us with all of the stuff we have. So it was really trying to figure out the answers to those questions: Why did these things happen, and why are they like that? That led me to search for the answers in lots of different locations.
So it really started off as kind of a personal quest, and it was written over the course of many years, much to the chagrin of my patient editors... but I was still re-evaluating, figuring out the answers.
How does your work – looking at human history through DNA – inform your views of the present and future?
What's very clear is that people are moving around and mixing to a much greater extent than we ever have. If you take a grand sweeping view of human genetic history, we start off in Africa as a relatively small population around seventy thousand years ago, and we nearly went extinct – dropped down to as few as two thousand people – so we start off together in this small group, and then we scattered and went all over the world over the course of the next two thousand generations. What's happened in the last couple hundred years is that people have started to come back together and to enter these melting pot cities. So the idea of the future, in the most obvious way, is that our genetic futures are becoming ever more closely intertwined. We did a film a couple years ago, which came out of the idea for an experiment where we wanted to test this in arguably the most diverse city in North America – Queens – and sample a couple hundred people in a single day and see how much diversity we could pick up. Could we actually see most of the world's major genetic lineages? And the answer is yes, we can. Look at Census data: for the first time in the year 2000, people were allowed to report multiple ethnicities and mixes of races whereas before you had to be either African American or Pacific Islander or Caucasian or whatever the categories were. You could report lots of different mixes and lots of people did that in the U.S., surprisingly large numbers, and that number has actually gone up in the 2010 Census. This is a continuing trend, an accelerating trend.
If we extrapolate the face of 2100, in ninety years, what will that look like? Well, it would be a melting pot face. It would be somebody with a little bit of African ancestry, a little European ancestry, Asian and Native American, and so that is what is going on all over the world to a greater or lesser degree. So the genetic prediction is that in the future we'll be much more closely connected to each other and share a lot more of our DNA than we have in the last sixty thousand years or so.
In addition, as I talked about in one of the chapters, in terms of traits and characteristics, we now have the ability with modern genetic technology to actually choose some of the traits that we want in our children. Of course, this is still a fairly expensive technology. The price will come down but it's always going to be something that is limited probably to the middle, upper-middle class and so on. And so what's going to happen when that's widely applied, and that's certainly the trajectory we seem to be on with the increasing use of IVF to have children, is that we are going to have this division in society between the "haves" and "have-nots." The haves are going to be able to choose the genes they want to put in their children. They're not going to have complete control, of course, you're limited by what actually shows up in the embryo panel that you create, but to the extent that people are using this technology, they will be able to give their children certain genetic advantages relative to other people. As a society we have to ask ourselves, is this the road we want to go down? If we do, do we want to make it available to everyone? Do we want to limit the sorts of choices we can make? Those are big questions.
What do you feel should be the limits of genetic power?
As I say in the book, I think we already utilize certain technologies and attributes to give our children advantages and I talk about tutors and orthodontists and all sorts of things. It's hard to legislate against things like that, which are already determined by money, but... I don't see us as a nation ever passing a law that would limit people's rights to utilize these technologies. Other countries might do it. Other countries that are more comfortable, perhaps, with government control of these industries and other aspects of life.
The contrast in the book is between the U.K., where the Whittakers weren't allowed to do what they wanted to do in terms of creating Jamie to serve as a donor for Charlie, and what's going on here. So it cuts both ways. To see that this little boy with a disease that would doom him to an early death will now live a long and happy life because his brother was born; I wouldn't want to legislate against that. But some of the other stuff, I don't know. I'm a little wary of some of the decisions that people might make. I would hope that people would have a kind of innate moral reaction to wanting to create a super race, Gattaca-like; people allowed to succeed and people who aren't. I'd like to think that we're above that as a society. So it remains to be seen how it's going to play out.
I guess what I was trying to do with that chapter of the book was just raise awareness of the fact that all of this stuff seems so futuristic, like in science fiction movies, when in fact it's been going on for over a decade now. It's happening out there and this is a debate we need to be engaged in as a society. And I, as a scientist, a writer, and an intellectual, cannot make these decisions on my own. As a society in a broader sense we need to be engaged in this debate in the same way we have to be engaged in how much we want to pay taxes and the debt ceiling which they're debating down the road from me right now. So yeah, these are big issues.
In Pandora's Seed, you talk about transgenerational forces, how our actions today may have unintended and unforeseen consequences for future generations. Do you think humans now are capable of the foresight necessary to respect transgenerational forces or do you think that the allure of present technology will trump any regard for future consequences?
In short, do I think we're capable of recognizing that these things will play out over the course of decades, hundreds of years, thousands of years, and react to that? No, unfortunately, because that's not the way we're wired. We're wired to deal with the here and now.
We all realize that the world is warming up. I'm sitting here in Washington, D.C. It's 104 degrees out today. It's the hottest day on record for this particular day. It's been the hottest July on record and most of the hottest years on record have occurred in the last two decades. We see this all over the world, and you can debate the extent to which what we're doing in terms of pumping greenhouse gases into the atmosphere is causing this. Personally, I believe the climate scientists that we are clearly playing a role. You can debate about that but you can't debate that things are warming up. It may be part of the longer term warming trend, but the issue is that these are things that we know are going to affect not only the lives of ourselves, but also the lives of our children and grandchildren, and our great-grandchildren. So what do we do to make the world livable for them? The problem is we have to make sacrifices in the here and now for this unknown benefit in the future, and we're just not capable of doing that calculus in our minds when there are other things going on like this recession... and high jobless rates and all these other things. We say, well you know, we just can't afford to deal with this stuff right now. When in fact these are things that need to be included in the broader calculations about the costs of activity or inactivity on a lot of these issues.
I think it's great that Obama has enacted these new fuel efficiency rules for cars, but it's going to cost a lot of money to get up to an average MPG of fifty-five. That's a huge shift from what we have today, double for most of the car manufacturers. That's going to cost everybody a lot of money. It's going to mean higher taxes and higher prices for cars because new technologies will have to be created and implemented. You're going to have to pay for it when you buy a new automobile. But it's a sign that at least the state is recognizing that there is a cost to inaction. And it's going to get a lot of opposition from industry groups and from political groups that don't want to believe that we're playing a role in climate change and that these things are important. But I think those sorts of shifts in thinking are the way you start to move forward on this front. You start to recognize that you have to be willing to pay a price now to do something that's better for the world in the long run.
How can you reconcile wanting to allow everyone to have freedoms, such as choosing the number of children they have or which car they own, with making decisions now that will help in the long term?
Again, I think it has to do with recognizing a cost to a completely libertarian attitude about the here and now. If you think that you should have unfettered access to anything and everyone should burn through resources at the greatest rate possible because you're not really going to have an effect on things... it's very clear that that's not the case. It might have been the case when there were 100 million people living on the planet. Then everybody could drive a gas guzzling SUV and it wouldn't cause any problems. But we're almost at seven billion... the numbers will go up to nine, nine and a half billion, by the middle of the century, and what's happening at the same time is that the developing world is going from being very poor, [using] very little energy because they don't have access to a lot of these things we take for granted, to wanting to have [those things] and actually being able to have them. It's simply untenable for everybody to lead the lives that we lead in the United States because we're a rich country.
We're all connected to generations of the past and future, we're all connected to each other, and we are in this together. We as a society, as a globe, as a global group of human beings, need to make decisions about where we're headed. We have this tremendous power, the idea of transgenerational power. The decisions of a group of hunter-gatherers, when they lived in the Savannah in Africa 100,000 years ago, had very few consequences for anybody coming after them. They just didn't have access to technologies that can do what we can do today. Things have completely changed now, and we have much more power than we probably should have given how far our brains have evolved. So I really think it's about that shift in thinking and recognizing, again, that we're connected to everybody that has come before, will come after, and everybody all over the world.
Do you think humans thousands of years from now will be able to see evidence of the rise of obesity and diabetes in our genomes? Have our genes been responding at all to our changing lifestyles or are the mutation rates such that you can't really tell that at this point?
Almost certainly mutations are being selected for and against by this current environment that we're in because that's happened throughout history. For instance, some of the genes that predispose to obesity, childhood or adult-onset diabetes, which now appears to be Type 2 diabetes, which – particularly if you have it relatively young – is going to mean that you're not going to be very healthy and you may have some sort of reproductive disadvantage... that's how selection works, if you have a reproductive advantage or disadvantage. It's possible that some of those genes could be selected against. In that case, we would start to see that in our descendants tens or hundreds of generations in the future because these events can happen quite quickly. Selection can be quite strong. So yes, it's entirely conceivable that we are selecting for traits in ourselves that our descendants in the year 4000, if we're still around, might be able to see evidence of... so we're still changing our own DNA.
In Pandora's Seed, you break down humans' understanding of the world into two main views: the logos and the mythos. How would you categorize humans' perceptions of nature?
I think it is a combination of things. You can view nature as something to be exploited, and we've always used it to a certain extent in that way. It provides us with food, shelter and materials that we need... medicines and wood to build our houses and so on. So that's kind of the logos attitude toward nature, but in addition, I think there is a mythos attitude towards nature. Psychologists have written about something that they call Nature Deficit Disorder among kids today: the idea that they don't get out into the wild as often as my generation used to or my parents' generation used to.
I just came back from taking my family on a drive through the Southwest. We went to a lot of the national parks in Colorado, Utah and Arizona that I visited as a kid, and it was great to get the kids out in nature and see them running around and finding things rather than sitting and looking at stuff on the screen. You can learn about a lot of this stuff online, but experiencing it is different, and I think that's a very important experience for kids to have. I think that's how they bond with nature and how they come to appreciate the notion of conservation and preserving biodiversity and the animals and the plants and the balance in the ecosystem... hopefully [our children] are willing to make sacrifices to ensure that these things do stick around and that their children will be able to understand them and appreciate them in the future in that same visceral kind of way. So I think humans experience nature in both ways and that they're both important.
Do you think we would respect the earth more with a sort of mythos-centered view?
I think there can be pragmatic reasons for wanting to preserve diversity, and one of the key components of the Genographic Project, for instance, is called the Legacy Fund. This is a grant-giving part of the project where we take the money that we raise from selling kits to the general public... we put it back into cultural preservation projects of indigenous groups all over the world, and this, of course, is aimed at preserving primarily human cultures. One of the projects that we funded recently that I like to talk about – because it's an example of one of the pragmatic reasons to preserve biodiversity – is with the Shuar people in Ecuador who live up in the high Andes. It's a project to help them catalog all of the plants and their knowledge of the various uses. And of course a lot of the plants are medicinal. And in fact a lot of the medicines that are prescribed today in our very advanced medical and technological world come from plant sources. And we know about a lot of these plant sources because of this accumulated indigenous knowledge and once that knowledge is gone and once the plants themselves are gone, how many potential treatments for cancer, HIV, or whatever you want to imagine, might we be losing out on? So there are pragmatic reasons as well... but I think in general yes, the mythos view, this romantic notion of "we need to live in harmony with nature" is important, and it's one that I think we are losing, certainly in Western society. I think it's happening all over the world as people again, are moving to cities and they leave countrysides behind and the countryside stops mattering to their kids and their grandkids because they never experience it, they don't see the importance of it. And that does worry me. It does concern me that we're going through this shift as a species.
Do you think there's a relationship between the rise of mental illness and obesity and humans' weakening connections with nature?
Certainly that could be the case. Absolutely. I don't know of any hard and fast scientific data because I don't research it extensively. We've lived a certain way for most of our evolutionary history as a species, that is how our brains evolved to interact with the world, and we are living in a profoundly different way today. I don't think that our brains have evolved quickly enough to catch up to particularly what's happened since the industrial revolution, in the last couple hundred years, which is where you see some of the most profound shifts and so I think that could play a role in it. Absolutely. I think that the loss of exposure to nature, interactions with nature, respect for nature, could certainly play a role in this sense of unease or mental illness, however you want to characterize it.
You're the director of the Genographic Project. Could you explain a little about the project?
What we look at are things called genetic markers and these are little changes in the DNA sequence that you're carrying around inside your body. As that genome, or DNA sequence, is being copied to be passed on to the next generation, they're like little typos because the sum total of the genome is very, very long, about six billion base pairs in length... it's like copying the longest text you can imagine. So imagine War and Peace, but multiply that by a thousand and you're copying this by hand. Inevitably, you're going to make a typo as it's being copied, and this happens at the DNA level as well. We call them mutations. And most of them have no effect at all on your fitness or on any trait. They're simply evolutionary baggage that's transmitted from one generation to the next. So by looking at how we share these mutations or how they've been passed down through the generations... how we share these patterns of genetic markers with other people, we can connect people into branches on what is effectively a family tree for everybody alive today. So by looking at these markers we can place people somewhere into this phylogenetic network of how we're all connected to each other. And by looking at those accumulated levels of diversity in various locations around the globe, we can actually start to map out the order in which these things occurred, when they occurred, and how they moved from Point A to Point B.
And so in order to do that you have to have as wide a sample of humanity's diversity as possible. So when we were doing those experiments and stuff... we're looking at two thousand people at most all over the world, and that's not a very good sample of humanity's diversity. There are six thousand languages spoken on the planet and we come in all different shapes, sizes, and colors and have this innate sense that we are an incredibly diverse species. Again, there are billions of us, so a few thousand is not a very good sample size. So that was the impetus behind the project which was essentially to sample humanity's diversity properly and to study people from all over the world, hundreds of thousands of people, and to really start to piece together the details of these ancient migratory journeys. So that's what we're doing in a nutshell. We're using the tools of a very modern, high-tech science, molecular genetics, to answer age-old questions, which really come down to: Who are we? Where do we come from?
Where do you see this information being applied in the future?
I don't know how much of a practical application it has. Certainly medical geneticists take it into account when they're designing experiments to map disease genes, genetic variants that predispose to common diseases and so on, because it's important just in terms of population stratification, the technical details of how you design these studies and that is something about how populations are related. So for practical purposes, it is somewhat useful in that sense but really it's part of knowing who we are as a species, in my mind. The only sentient species that we're aware of certainly that's been capable of evolving to the point where it can begin to answer questions about its own origins using the tools of science is huge. As I've said throughout the project since we launched it in 2005, there is a sense of urgency to this because of this whole shift in human migration and the idea that we're losing and mixing to a much greater extent. So the groups that give us an insight into the ancient history of their geographic location, the indigenous groups, are being absorbed into this melting pot and so we're losing the footprints of our ancestors in the continuum of the people of the world. So there's a closing window of opportunity in which to do this. Of the samples that we've collected so far, nearly half a million, about 74,000 of those are from indigenous populations all over the world. That's like a genetic snapshot of who our species is. The genetic history of our species summarized in this collection of samples [is] a tremendous resource to have moving forward. It's not unlike the seed banks that people have created to preserve agricultural diversity to be able to study it and hopefully say something about where crops have come from and where they might be going. So that's really the scientific, pragmatic application of it.
There's a broader sociological implication as well with all the work we do. The idea that we emerged from Africa in the last sixty thousand years, only two thousand human generations [ago], and that we were all members of a single mixing population prior to that, shows that old-fashioned concepts of race are simply wrong. The idea that there are deep-seated biological differences between different population groups, continental groups, or races, whatever you want to call them, is simply not the case. We're 99.9 precent identical at the DNA level and we're all connected to each other much more closely than we ever suspected. So we're effectively members of a single extended human family.
You discuss many issues in Pandora's Seed, all of which are very relevant and pressing to today. Of these issues, which do you think is most critical that the greater public understands?
I think it is the shift in thinking from simply worrying about the short term to worrying about the long term. I think that's the most pressing change that needs to take place. I think if we can come to terms with this whole notion of transgenerational power, unintended consequences, whatever you want to call it, but this notion of "what we do today affects things many years down the road," whether it's climate change or what we're doing in terms of choosing genes for our children. I think we would achieve some level of resolution on so many of these issues if we came to accept and understand that the things we're doing today do have longer term consequences and took those into account when we were trying to design solutions.
Photos are copyright protected and may not be reproduced without permission. Images are used with the permission of Flickr Creative Commons Attribution License 2.0 Generic; copyright information for images is as follows: 1) Spencer Wells, photo courtesy of Erik Hersman; 2) Rally for the Right to Know, photo courtesy of Alexis Bayden-Mayer and Millions Against Monsanto; 3) Genetically Engineered Guava, photo courtesy of Yun Huang Yong; 4) Canola Cultivation, photo courtesy of Jan Smith; 5) Rally for the Right to Know II, photo courtesy of Alexis Bayden-Mayer and Millions Against Monsanto; 6) Tomato, photo courtesy of Joost J. Bakker.