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Video transcript

In Northern Tanzania there's a place called Laetoli. Most tourist who go to that region go to the Serengeti and other big national parks, go right by Laetoli because at first glance it's an unremarkable bit of savannah. But what makes Laetoli special is that laid out in volcanic ash are footprints. Footprints made by early hominids, early ancestors of humans that were laid down over 3.5 million years ago. Now, to me what makes this place really special is not just the hominid prints but also all the other prints that surround these footprints. They're prints of lots of other kinds of animals that lived there. So you see hyena prints, an extinct form of elephant, wild boar and many other species, actually 20 other species of animals crisscrossing these early proto-human prints, if you will. It makes you realize that as long as humans have been on this planet, we have been part of and interacting with nature. And sure enough we've modified nature in all sorts of ways. We clear grasslands by burning them, we cut down forests and have been doing so for a long time, we've domesticated animals like horses and dogs. And all those things have had a big impact on the planet, we've caused extinctions of species in the Pleistocene, big mammals like the mastodon and the mammoth. And with that kind of extinction, the extinction of these big mammals, we might have even tampered with the atmosphere. Those animals produced methane. When we wiped them out we reduced the concentration of methane in the atmosphere. So humans have been a huge influence on the planet and nature and we've been part of it. Then came agriculture. And with agriculture and the settlement of cities came specialization. When we started specializing on one particular kind of job, we started divorcing ourselves from nature. The guy who makes the wheel no longer needs to know where his water comes from or where food comes from, he can simply trade that wheel for food. And that is continued all the way into the industrial era. Go out on the street today and ask someone, "Where does your water come from?" What are they gonna tell you? They're gonna say, "The tap," right? They're not gonna really think about the river. So the pendulum has swung all the way from connection with nature to disconnection with nature but now it's starting to swing back again for three interesting reasons. Reason one is that science has come up to a point where we can really understand the impacts we're having on the planet. The second is social networks. Social networks today are allowing us to collaborate and create collective action and also understand collective impacts around the planet. So something that's happening to me here, I can communicate with and compare with what's happening in China for example in real time. And the third reason is we're a planet with seven billion people heading to ten billion. When you have that many people, every impact is gonna have a ripple effect. So those three reasons are really causing the pendulum to sort of shift back today and once again make us rethink our connection to nature. And so seeing humans as separate from nature, we're starting to once again understand that nature in some ways is the ultimate social network and we humans are very much part of it. Now, nothing brings to me that point or illustrates that point better than those photographs that came to Earth from those Apollo astronauts. So when the astronauts went out to space and took those photographs, all of a sudden we could see the whole planet. We could see all of planet Earth for the first time in the history of humans. In fact, in the history of any species that has ever lived on the planet. That moment to me really symbolizes this next era that we're going into. An era where our eyes are opened to the impact that we can have but we also have the opportunity now to do something about it and to do something about it at a planetary scale. So how do I feel about the future? Here's what I think. I think technology will really help us to a great deal in moving us forward and solving some of the big, intractable problems we have today. But really and most importantly I think what's going on is right now we have that window, that narrow window in time where pretty much any problem that we can see, we can start to understand it, fully understand it, and also have the opportunity to do something about it. When it comes to population with seven billion we'll probably end up at ten maybe 11 billion, but most scientists agree that we're going to start leveling off and population will eventually be stable. The one part that we don't really know much about is consumption, how much we consume and we consume all this stuff not just because we need it, but because we think it actually makes us feel happy. It's a really weird thing. So it turns out that virtually any way you can measure human well-being, whether it's healthcare or education or how long will you live, things have been getting better. But when it comes to happiness, it's not so clear. Are we really happy than we... than our parents were and were they really happier than, you know, several generations ago. That's a harder question to answer. If we can divorce now our need for consumption as the driver towards happiness, then I think we really have a chance of not just living and fulfilling our aspirations on this planet but doing so in a way in which that can really make us feel happy as well as make sure there's enough space for everyone else.