TED日本語 - フアン・エンリケス: 我々の子孫は別の種になる？

All right. So, like all good stories, this starts a long, long time ago when there was basically nothing. So here is a complete picture of the universe about 14-odd billion years ago. All energy is concentrated into a single point of energy. For some reason it explodes, and you begin to get these things. So you're now about 14 billion years into this. And these things expand and expand and expand into these giant galaxies, and you get trillions of them. And within these galaxies you get these enormous dust clouds. And I want you to pay particular attention to the three little prongs

in the center of this picture. If you take a close-up of those, they look like this. And what you're looking at is columns of dust where there's so much dust -- by the way, the scale of this is a trillion vertical miles -- and what's happening is there's so much dust, it comes together and it fuses and ignites a thermonuclear reaction. And so what you're watching is the birth of stars. These are stars being born out of here. When enough stars come out, they create a galaxy. This one happens to be a particularly important galaxy, because you are here. (Laughter) And as you take a close-up of this galaxy, you find a relatively normal, not particularly interesting star.

By the way, you're now about two-thirds of the way into this story. So this star doesn't even appear until about two-thirds of the way into this story. And then what happens is there's enough dust left over that it doesn't ignite into a star, it becomes a planet. And this is about a little over four billion years ago.

And soon thereafter there's enough material left over that you get a primordial soup, and that creates life. And life starts to expand and expand and expand, until it goes kaput.

(Laughter)

Now the really strange thing is life goes kaput, not once, not twice, but five times. So almost all life on Earth is wiped out about five times. And as you're thinking about that, what happens is you get more and more complexity, more and more stuff to build new things with. And we don't appear until about 99.96 percent of the time into this story, just to put ourselves and our ancestors in perspective.

So within that context, there's two theories of the case as to why we're all here. The first theory of the case is that's all she wrote. Under that theory, we are the be-all and end-all of all creation. And the reason for trillions of galaxies, sextillions of planets, is to create something that looks like that and something that looks like that. And that's the purpose of the universe; and then it flat-lines, it doesn't get any better.

(Laughter)

The only question you might want to ask yourself is, could that be just mildly arrogant? And if it is -- and particularly given the fact that we came very close to extinction. There were only about 2,000 of our species left. A few more weeks without rain, we would have never seen any of these.

(Laughter)

(Applause)

So maybe you have to think about a second theory if the first one isn't good enough. Second theory is: Could we upgrade? (Laughter) Well, why would one ask a question like that? Because there have been at least 29 upgrades so far of humanoids. So it turns out that we have upgraded. We've upgraded time and again and again. And it turns out that we keep discovering upgrades. We found this one last year. We found another one last month.

And as you're thinking about this, you might also ask the question: So why a single human species? Wouldn't it be really odd if you went to Africa and Asia and Antarctica and found exactly the same bird -- particularly given that we co-existed at the same time with at least eight other versions of humanoid at the same time on this planet? So the normal state of affairs is not to have just a Homo sapiens; the normal state of affairs is to have various versions of humans walking around.

And if that is the normal state of affairs, then you might ask yourself, all right, so if we want to create something else, how big does a mutation have to be? Well Svante Paabo has the answer. The difference between humans and Neanderthal is 0.004 percent of gene code. That's how big the difference is one species to another. This explains most contemporary political debates.

(Laughter)

But as you're thinking about this,one of the interesting things is how small these mutations are and where they take place. Difference human/Neanderthal is sperm and testis, smell and skin. And those are the specific genes that differ from one to the other. So very small changes can have a big impact.

And as you're thinking about this, we're continuing to mutate. So about 10,000 years ago by the Black Sea, we had one mutation in one gene which led to blue eyes. And this is continuing and continuing and continuing.

And as it continues,one of the things that's going to happen this year is we're going to discover the first 10,000 human genomes, because it's gotten cheap enough to do the gene sequencing. And when we find these, we may find differences.

And by the way, this is not a debate that we're ready for, because we have really misused the science in this. In the 1920s, we thought there were major differences between people. That was partly based on Francis Galton's work. He was Darwin's cousin. But the U.S., the Carnegie Institute, Stanford, American Neurological Association took this really far. That got exported and was really misused. In fact, it led to some absolutely horrendous treatment of human beings. So since the 1940s, we've been saying there are no differences, we're all identical. We're going to know at year end if that is true.

And as we think about that, we're actually beginning to find things like, do you have an ACE gene? Why would that matter? Because nobody's ever climbed an 8, 000-meter peak without oxygen that doesn't have an ACE gene. And if you want to get more specific, how about a 577R genotype? Well it turns out that every male Olympic power athelete ever tested carries at least one of these variants.

If that is true, it leads to some very complicated questions for the London Olympics. Three options: Do you want the Olympics to be a showcase for really hardworking mutants? (Laughter) Option number two: Why don't we play it like golf or sailing? Because you have one and you don't have one, I'll give you a tenth of a second head start. Version number three: Because this is a naturally occurring gene and you've got it and you didn't pick the right parents, you get the right to upgrade. Three different options. If these differences are the difference between an Olympic medal and a non-Olympic medal.

And it turns out that as we discover these things, we human beings really like to change how we look, how we act, what our bodies do. And we had about 10.2 million plastic surgeries in the United States, except that with the technologies that are coming online today, today's corrections, deletions, augmentations and enhancements are going to seem like child's play.

You already saw the work by Tony Atala on TED, but this ability to start filling things like inkjet cartridges with cells are allowing us to print skin, organs and a whole series of other body parts. And as these technologies go forward, you keep seeing this, you keep seeing this, you keep seeing things -- 2000, human genome sequence -- and it seems like nothing's happening, until it does. And we may just be in some of these weeks.

And as you're thinking about these two guys sequencing a human genome in 2000 and the Public Project sequencing the human genome in 2000, then you don't hear a lot, until you hear about an experiment last year in China, where they take skin cells from this mouse, put four chemicals on it, turn those skin cells into stem cells, let the stem cells grow and create a full copy of that mouse.

That's a big deal. Because in essence what it means is you can take a cell, which is a pluripotent stem cell, which is like a skier at the top of a mountain, and those two skiers become two pluripotent stem cells,four,eight,16, and then it gets so crowded after 16 divisions that those cells have to differentiate. So they go down one side of the mountain, they go down another. And as they pick that, these become bone, and then they pick another road and these become platelets, and these become macrophages, and these become T cells. But it's really hard, once you ski down, to get back up. Unless, of course, if you have a ski lift. And what those four chemicals do is they take any cell and take it way back up the mountain so it can become any body part.

And as you think of that, what it means is potentially you can rebuild a full copy of any organism out of any one of its cells. That turns out to be a big deal because now you can take, not just mouse cells, but you can human skin cells and turn them into human stem cells. And then what they did in October is they took skin cells, turned them into stem cells and began to turn them into liver cells. So in theory, you could grow any organ from any one of your cells.

Here's a second experiment: If you could photocopy your body, maybe you also want to take your mind. And one of the things you saw at TED about a year and a half ago was this guy. And he gave a wonderful technical talk. He's a professor at MIT. But in essence what he said is you can take retroviruses, which get inside brain cells of mice. You can tag them with proteins that light up when you light them. And you can map the exact pathways when a mouse sees, feels, touches, remembers, loves. And then you can take a fiber optic cable and light up some of the same things. And by the way, as you do this, you can image it in two colors, which means you can download this information as binary code directly into a computer.

So what's the bottom line on that? Well it's not completely inconceivable that someday you'll be able to download your own memories, maybe into a new body. And maybe you can upload other people's memories as well. And this might have just one or two small ethical, political, moral implications. (Laughter) Just a thought.

Here's the kind of questions that are becoming interesting questions for philosophers, for governing people, for economists, for scientists. Because these technologies are moving really quickly.

And as you think about it, let me close with an example of the brain. The first place where you would expect to see enormous evolutionary pressure today, both because of the inputs, which are becoming massive, and because of the plasticity of the organ, is the brain.

Do we have any evidence that that is happening? Well let's take a look at something like autism incidence per thousand. Here's what it looks like in 2000. Here's what it looks like in 2002,2006,2008. Here's the increase in less than a decade. And we still don't know why this is happening. What we do know is, potentially, the brain is reacting in a hyperactive, hyper-plastic way, and creating individuals that are like this. And this is only one of the conditions that's out there. You've also got people with who are extraordinarily smart, people who can remember everything they've seen in their lives, people who've got synesthesia, people who've got schizophrenia. You've got all kinds of stuff going on out there, and we still don't understand how and why this is happening.

But one question you might want to ask is, are we seeing a rapid evolution of the brain and of how we process data? Because when you think of how much data's coming into our brains, we're trying to take in as much data in a day as people used to take in in a lifetime. And as you're thinking about this, there's four theories as to why this might be going on, plus a whole series of others. I don't have a good answer. There really needs to be more research on this.

One option is the fast food fetish. There's beginning to be some evidence that obesity and diet have something to do with gene modifications, which may or may not have an impact on how the brain of an infant works.

A second option is the sexy geek option. These conditions are highly rare. (Laughter) (Applause) But what's beginning to happen is because these geeks are all getting together, because they are highly qualified for computer programming and it is highly remunerated, as well as other very detail-oriented tasks, that they are concentrating geographically and finding like-minded mates. So this is the assortative mating hypothesis of these genes reinforcing one another in these structures.

The third, is this too much information? We're trying to process so much stuff that some people get synesthetic and just have huge pipes that remember everything. Other people get hyper-sensitive to the amount of information. Other people react with various psychological conditions or reactions to this information. Or maybe it's chemicals.

But when you see an increase of that order of magnitude in a condition, either you're not measuring it right or there's something going on very quickly, and it may be evolution in real time.

Here's the bottom line. What I think we are doing is we're transitioning as a species. And I didn't think this when Steve Gullans and I started writing together. I think we're transitioning into Homo evolutis that, for better or worse, is not just a hominid that's conscious of his or her environment, it's a hominid that's beginning to directly and deliberately control the evolution of its own species, of bacteria, of plants, of animals. And I think that's such an order of magnitude change that your grandkids or your great-grandkids may be a species very different from you.

Thank you very much.

(Applause)