Top 100 Stories of 2010 No. 3: E.O. Wilson's Theory of Altruism Shakes Up Understanding of Evolution
//discovermagazine.com/2011/jan-feb/03
In 1975 Harvard biologist E. O. Wilson published Sociobiology, perhaps the most powerful refinement of evolutionary theory since On the Origin of Species. Darwins theory of natural selection postulated a brutal world in which individuals vied for dominance. Wilson promoted a new perspective: Social behaviors were often genetically programmed into species to help them survive, he said, with altruism self-destructive behavior performed for the benefit of othersbred into their bones.
In the context of Darwinian selection, such selflessness hardly made sense. If you sacrificed your life for another and extinguished your genes, wouldnt the engine of evolution simply pass you by? Wilson resolved the paradox by drawing on the theory of kin selection. According to this way of thinking, altruistic individuals could emerge victorious because the genes that they share with kin would be passed on. Since the whole clan is included in the genetic victory of a few, the phenomenon of beneficial altruism came to be known as inclusive fitness. By the 1990s it had become a core concept of biology, sociology, even pop psychology.
So the scientific world quaked last August when Wilson renounced the theory that he had made famous. He and two Harvard colleagues, Martin Nowak and Corina Tarnita, reported in Nature that the mathematical construct on which inclusive fitness was based crumbles under closer scrutiny. The new work indicates that self-sacrifice to protect a relations genes does not drive evolution. In human terms, family is not so important after all; altruism emerges to protect social groups whether they are kin or not. When people compete against each other they are selfish, but when group selection becomes important, then the altruism characteristic of human societies kicks in, Wilson says. We may be the only species intelligent enough to strike a balance between individual and group-level selection, but we are far from perfect at it. The conflict between the different levels may produce the great dramas of our species: the alliances, the love affairs, and the wars.
When you published Sociobiology in 1975, you faced enormous resistance, especially to the implication that human nature was genetically based. Now your colleagues are defending one of key tenets in your bookkin selectionwhile you try to dismantle it. What do you make of the shifting attitudes in your field? Interesting, isnt it? But Im not so sure I pivoted that much on kin selection in Sociobiology. If you look at the opening pages, I had a diagram showing how a future science of sociobiology would be built. Kin selection was a nice little part of it in 1975, but Sociobiology went way beyond that. It goes into demography: how groups are formed, how they compete, how communication evolves. Together with ecology and population genetics, it all formed a framework to help explain the origin of social behavior.
Yet a generation of sociobiologists built their research around the idea of kin selection. How did that happen? They were enchanted by kin selection because it appeared to have a basis in mathematics. It seemed solid and it looked good. It was glamorous.
Your new paper states that the mathematical underpinning of kin selection, called the Hamilton inequality, does not work. Why not? When analyzed to the bottom of its assumptionswhen we ask under what conditions it could holdit applies only to a very narrow set of parameters that dont actually exist on Earth. Inclusive fitness turns out to be a phantom measure that cannot be obtained.
If inclusive fitness is wrong, how do you explain eusocialitywhen individuals reduce their ability to have offspring of their own to raise the offspring of others? It turns out that theres only one condition that has to be reached in the course of evolution for eusociality to emerge: A mother or father must raise their young within reach of adequate resources at a defensible nest. Getting from the solitary lifestyle to one that includes a defensible nest can be done in one evolutionary stepone gene change. This turns the concept of inclusive fitness on its head, because the gene change and the social behavior came first. Kinship is a consequence of that, not a cause.
How do these ideas play out in the natural world? Lets take the example of a bird with helpers at the nest. Supporters of inclusive fitness point to a correlation between the amount of help that the young birds give when they stay at home and how closely they are related to the parents and each other. But the young birds are looking after their extended family only until they have families of their own. By analogy, you might stay home and baby-sit for younger siblings after college, but its not out of a sense of kinship toward them. Its because it makes financial sense until you find a job and move out. What these researchers unwittingly do not mention in their studies is that cases of inclusive fitness are quite unusual in an important way. Each of the bird species lives in an area where nest sites and territories are very scarce, very hard for young birds to get.
Can you give an example of such overinterpretation? I recently had the opportunity to visit an endangered species called the red-cockaded woodpecker in Florida. This is the only species in the world that drills nests in live trees. Why do these birds drill in live trees? Because when they enter the tree it exudes large amounts of sticky sap all around the entrance hole. The birds can fly in and out, but their principal predator, the rat snake, is prevented from entering by this sticky mess. Now, finding the right kind of tree and drilling the hole takes a long time, as much as a year, for a young male red-cockaded woodpecker. It is to his advantage to stay with his parents and help them out while he is doing that. Maybe there is some kin selection going there, but thats not whats causing the behavior of staying at home and helping. When the young male completes his hole, he courts a female, they move in, and they start a nest there of their own. That is the incentive that keeps him there.
How would you interpret this behavior within your new framework? The alternative hypothesis is that it is to the advantage of kids to stay at home until they can find a place to go. This is called the anticipation of inheritance. If Mom or Dad dies, youve got their nest and their territory. If they dont, you stay, and its to your advantage to help, and its to their advantage to have your help until you can get a territory of your own. Basic natural selection explains it; no kin selection required.
Seen that way, it is difficult to understand why anyone attributed this kind of behavior to kin selection in the first place. Thats what I point out in our Nature critique. Researchers have gone at it backward. Instead of studying whats going on and seeking the best explanation, they start by looking for a test to demonstrate its really kin selection.
What about the classic kin-selection example, worker bees sacrificing themselves for their queen? How else can you explain that? The best way to think of what has been called altruism in social insects is to return to an individual level of selection: that is, queen to queen. Think of the workers as robots and near-replicants of the queen herself. From the beginning these subordinate replicants are just extensions of the queen. It really is queen against queen, since they are the only ones that produce offspring.
But whether or not bees are altruistic, altruism certainly exists in humans. Humans are different because we seem to have true multilevel selection (pdf). On one level, individual selection goes on inside groups, with people competing against each other and producing what we think of as selfish behavior. On another level, selection goes on between groups. Group selection tends to reinforce altruistic behavior in individuals because without altruistic individuals, the group is at a disadvantage in competition and combat with other groups. But that is not kin selection.
It seems as if kin selection could actually damage the group. For instance, nepotism weakens a group, doesnt it? n the level of the group, nepotism is counter-evolutionary. A group of altruists will beat a society of selfish individuals every time. Group selection favors biological traits like communication and cooperation that are needed for the group to remain cohesive and powerful. In humans, theres a constant struggle between group selection and individual selection that is unique. Humans managed to find a way to strike a balance. It took a lot of intelligence, but that is a story for another day.
From an evolutionary perspective, then, does kinship matter at all in humans? You can have kin selection incidentally. You can certainly increase your genes by giving up your job and your marriage and taking care of your sisters kids. If you did it very well, that could result in an increase in your genes. But my point is that it doesnt lead anywhere in terms of evolution. Inclusive fitness theory said that social behavior advances because kin find one another and bond together to spread their genes, and then a society emerges. But Im afraid its the other way around. When people bond together, kin or not, they can become competitive as a group.
Despite all this, your colleagues are digging in and defending kin selection with passion. How do you respond? Its gonna be a battle royaland not pretty. You might know Schopenhauers three stages of response to a new idea. The three are one, ridicule, and Ive been through that already. Two, outrage. And three, the declaration that its obvious.
You seem to be passing through stage two right now. One letter to Nature is signed by 144 people. Their argument has been around for four decades, but nothing in the letter addresses the challenges we raised: that the mathematical ground of inclusive fitness theory is unsound and that, when you compare competing hypotheses, outcomes are much more directly and convincingly explained by mainstream natural selection.
But for now it seems like the bulk of scientific opinion is against you. Science is not done by polling. Have you ever heard of 100 Scientists Against Einstein? It was a pamphlet signed by 100 physicists to overthrow his theory of relativity. After they published it, Einstein remarked, Why 100 authors? If I were wrong, then one would have been enough!
Your new take on evolutionary theory seems to echo an older view of human nature: more about competition, less about compassion. Do you agree? If you look at the humanities and much of the creative artsespecially the dramatic stories of war, alliance, and lovemany literary themes describe the conflict between group and individual selection. When we look at human evolution in this new way, its going to be much more productive. We now have solid grounding for explaining our social behaviors in terms of the multiple levels of selection that actually occur.
Amit Sood: Building a museum of museums on the web
My name is Amit. And 18 months ago, I had another job at Google, and I pitched this idea of doing something with museums and art to my boss who's actually here, and she allowed me to do it. And it took 18 months. A lot of fun negotiations and stories, I can tell you, with 17 very interesting museums from nine countries. But I'm going to focus on the demo. There are a lot of stories about why we did this.
I think my personal story is explained very simply on the slide, and it's access. And I grew up in India. I had a great education -- I'm not complaining -- but I didn't have access to a lot of these museums and these artworks. And so when I started traveling and going to these museums, I started learning a lot. And while working at Google, I try to put this desire to make it more accessible with technology together. So we formed a team, a great team of people, and we started doing this.
I'm going to probably get into the demo and then tell you a couple of the interesting things we've had since launch. So, simple: you come to GoogleArtProject.com. You look around at all these museums here. You've got the Uffizi, you've got the MoMA, the Hermitage, the Rijks, the Van Gogh. I'm going to actually get to one of my favorites, the Metropolitan Museum of Art in New York. Two ways of going in -- very simple. Click and, bang, you're in this museum. It doesn't matter where you are -- Bombay, Mexico, it doesn't really matter. You move around, you have fun. You want to navigate around the museum? Open the plan up, and, in one click, jump. You're in there, you want to go to the end of the corridor. Keep going. Have fun. Explore.
(Applause)
Thanks. I haven't come to the best part.
(Laughter)
So now I'm in front of one of my favorite paintings, The Harvesters by Pieter Breugel at the Met. I see this plus sign. If the museum has given us the image, you click on it. Now this is one of the images. So this is all of the meta-data information. For those of you who are truly interested in art, you can click this -- but I'm going to click this off right now. And this is one of these images that we captured in what we call gigapixel technology. So this image, for example, has closed to, I think, around 10 billion pixels. And I get a lot of people asking me: "What do you get for 10 billion pixels?" So I'm going to try to show you what you really get for 10 billion pixels. You can zoom around very simply. You see some fun stuff happening here. I love this guy; his expression is priceless.
But then you really want to go deep. And so I started playing around, and I found something going on over here. And I was like, "Hold on. That sounds interesting." Went in, and I started noticing that these kids were actually beating something. I did a little research, spoke to a couple of my contacts at the Met, and actually found out that this is a game called squail, which involves beating a goose with a stick on Shrove Tuesday. And apparently it was quite popular. I don't know why they did it, but I learned something about it. Now just to get really deep in, you can really get to the cracks. Now just to give you some perspective, I'm going to zoom out, so you really see what you get. Here is where we were, and this is the painting.
(Applause)
The best is yet to come -- so in a second. So now let's just quickly jump into the MoMA, again in New York. So another one of my favorites, The Starry Night. Now the example I showed you was all about finding details. But what if you want to see brush strokes? And what if you want to see how Van Gogh actually created this masterpiece? You zoom in. You really go in. I'm going to go to one of my favorite parts in this painting, And I'm really going to get to the cracks. This is The Starry Night, I think, never seen like this before.
I'm going to show you my other favorite feature. There's a lot of other stuff here, but I don't have time. This is the real cool part. It's called Collections. Anyone of you, anybody -- doesn't matter if you're rich, if you're poor, if you have a fancy house -- doesn't matter. You can go and create your own museum online -- create your own collection across all these images. Very simply, you go in -- and I've created this called The Power of Zoom -- you can just zoom around. This is The Ambassadors, based in the National Gallery. You can annotate the stuff, send it to your friends and really get a conversation going about what you're feeling when you go through these masterpieces.
So I think, in conclusion, for me, the main thing is that all the amazing stuff here does not really come from Google. It doesn't, in my opinion, even come from the museums. I probably shouldn't say that. It really comes from these artists. And that's been my humbling experience in this. I mean, I hope in this digital medium that we do justice to their artwork and represent it properly online. And the biggest question I get asked nowadays is, "Did you do this to replicate the experience of going to a museum?" And the answer is no. It's to supplement the experience.
Do you know that we have 1.4 million cellular radio masts deployed worldwide? And these are base stations. And we also have more than five billion of these devices here. These are cellular mobile phones. And with these mobile phones, we transmit more than 600 terabytes of data every month. This is a 6 with 14 zeroes -- a very large number. And wireless communications has become a utility like electricity and water. We use it everyday. We use it in our everyday lives now -- in our private lives, in our business lives. And we even have to be asked sometimes, very kindly, to switch off the mobile phone at events like this for good reasons. And it's this importance why I decided to look into the issues that this technology has, because it's so fundamental to our lives.
And one of the issues is capacity. The way we transmit wireless data is by using electromagnetic waves -- in particular, radio waves. And radio waves are limited. They are scarce; they are expensive; and we only have a certain range of it. And it's this limitation that doesn't cope with the demand of wireless data transmissions and the number of bytes and data which are transmitted every month. And they are simply running out of spectrum. There's another problem. That is efficiency. These 1.4 million cellular radio masts, or base stations, consume a lot of energy. And mind you, most of the energy is not used to transmit the radio waves, it is used to cool the base stations. Then the efficiency of such a base station is only at about five percent. And that creates a big problem. Then there's another issue that you're all aware of. You have to switch off your mobile phone during flights. In hospitals, they are security issues. And security is another issue. These radio waves penetrate through walls. They can be intercepted, and somebody can make use of your network if he has bad intentions.
So these are the main four issues. But on the other hand, we have 14 billion of these: light bulbs, light. And light is part of the electromagnetic spectrum. So let's look at this in the context of the entire electromagnetic spectrum, where we have gamma rays. You don't want to get close to gamma rays, it could be dangerous. X-rays, useful when you go to hospitals. Then there's ultraviolet light. it's good for a nice suntan, but otherwise dangerous for the human body. Infrared -- due to eye safety regulations, you can only use it with low power. And then we have the radio waves, they have the issues I've just mentioned. And in the middle there, we have this visible light spectrum. It's light, and light has been around for many millions of years. And in fact, it has created us, has created life, has created all the stuff of life. So it's inherently safe to use. And wouldn't it be great to use that for wireless communications.
Not only that, I compared it to the entire spectrum. I compared the radio waves spectrum -- the size of it -- with the size of the visible light spectrum. And guess what? We have 10,000 times more of that spectrum, which is there for us to use. So not only do we have this huge amount of spectrum, let's compare them with a number I've just mentioned. We have 1.4 million expensively deployed, inefficient radio cellular base stations. And multiply that by 10,000, then you end up at 14 billion. 14 billion is the number of light bulbs installed already. So we have the infrastructure there. Look at the ceiling, you see all these light bulbs. Go to the main floor, you see these light bulbs.
Can we use them for communications? Yes. What do we need to do? The one thing we need to do is we have to replace these inefficient incandescent light bulbs, florescent lights, with this new technology of LED, LED light bulbs. An LED is a semiconductor. It's an electronic device. And it has a very nice acute property. Its intensity can be modulated at very high speeds, and it can be switched off at very high speeds. And this is a fundamental basic property that we explored with our technology. So let's show how we do that. Let's go to the closest neighbor to the visible light spectrum -- go to remote controls. You all know remote controls have an infrared LED -- basically you switch on the LED, and if it's off, you switch it off. And it creates a simple, low-speed data stream in 10,000 bits per second, 20,000 bits per second. Not usable for a YouTube video.
What we have done is we have developed a technology with which we can furthermore replace the remote control of our light bulb. We transmit with our technology, not only a single data stream, we transmit thousands of data streams in parallel, at even higher speeds. And the technology we have developed -- it's called SIM OFDM. And it's spacial modulation -- these are the only technical terms, I'm not going into details -- but this is how we enabled that light source to transmit data.
You will say, "Okay, this is nice -- a slide created in 10 minutes." But not only that. What we've done is we have also developed a demonstrator. And I'm showing for the first time in public this visible light demonstrator. And what we have here is an ordinary desk lamp. We fit in an LED light bulb, worth three U.S. dollars, put in our signal processing technology. And then what we have here is a little hole. And the light goes through that hole. There's a receiver. The receiver will convert these little, subtle changes in the amplitude that we create there into an electrical signal. And that electrical signal is then converted back to a high-speed data stream. In the future we hope that we can integrate this little hole into these smart phones. And not only integrate a photo detector here, but maybe use the camera inside.
So what happens when I switch on that light? As you would expect, it's a light, a desk lamp. Put your book beneath it and you can read. It's illuminating the space. But at the same time, you see this video coming up here. And that's a video, a high-definition video that is transmitted through that light beam. You're critical. You think, "Ha, ha, ha. This is a smart academic doing a little bit of tricks here." But let me do this.
(Applause)
Once again. Still don't believe? It is this light that transmits this high-definition video in a split stream. And if you look at the light, it is illuminating as you would expect. You don't notice with your human eye. You don't notice the subtle changes in the amplitude that we impress onto this light bulb. It's serving the purpose of illumination, but at the same time, we are able to transmit this data. And you can just see, even light from the ceiling comes down here to the receiver. It can ignore that constant light, because all the receiver's interested in are subtle changes. You also have a critical question now and then. You say, "Okay, do I have to have the light on all the time to have this working?" And the answer is yes. But, you can dim down the light to a level that it appears to be off. And you are still able to transmit data -- that's possible.
So I've mentioned to you the four challenges. Capacity: We have 10,000 times more spectrum, 10,000 times more LEDs installed already in the infrastructure. You would agree with me, hopefully, there's no issue of capacity anymore. Efficiency: This is data through illumination -- it's first of all an illumination device. And if you do the energy budget, the data transmission comes for free -- highly energy efficient. I don't mention the high energy efficiency of these LED light bulbs. If the whole world would deploy them, you would save hundreds of power plants. That's aside.
And then I've mentioned the availability. You will agree with me that we have lights in the hospital. You need to see what to do. You have lights in an aircraft. So it's everywhere there is light. Look around. Everywhere. Look at your smart phone. It has a flashlight, an LED flashlight. These are potential sources for high-speed data transmission.
And then there's security. You would agree with me that light doesn't penetrate through walls. So no one, if I have a light here, if I have secure data, no one on the other side of this room through that wall would be able to read that data. And there's only data where there is light. So if I don't want that receiver to receive the data, then what I could do, turn it away. So the data goes in that direction, not there anymore. Now we can in fact see where the data is going to.
So for me, the applications of it, to me, are beyond imagination at the moment. We have had a century of very nice, smart application developers. And you only have to notice, where we have light, there is a potential way to transmit data. But I can give you a few examples. Well you may see the impact already now. This is a remote operated vehicle beneath the oceans. And they use light to illuminate space down there. And this light can be used to transmit wireless data that these things [use] to communicate with each other.
Intrinsically safe environments like this petrochemical plant -- you can't use RF, it may generate antenna sparks, but it can use light -- you see plenty of light there. In hospitals, for new medical instruments; in streets for traffic control. Cars have LED-based headlights, LED-based back lights, and cars can communicate with each other and prevent accidents in the way that they exchange information. Traffic lights can communicate to the car and so on. And then you have these millions of street lamps deployed around the world. And every street lamp would be a free access point. We call it, in fact, a Li-Fi, light-fidelity. And then we have these aircraft cabins. There are hundreds of lights in an aircraft cabin, and each of these lights could be a potential transmitter of wireless data. So you could enjoy your most favorite TED video on your long flight back home. Online life. So I think that is a vision that is possible.
So, all we would need to do is to fit a small microchip to every potential illumination device. And this would then combine two basic functionalities: illumination and wireless data transmission. And it's this symbiosis that I personally believe could solve the four essential problems that face us in wireless communication these days. And in the future, you would not only have 14 billion light bulbs, you may have 14 billion Li-Fis deployed worldwide -- for a cleaner, a greener, and even a brighter future.
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