The big question for this segment is, what is distinctive about the way that human beings innovate. [MUSIC] Humans are super innovators. It's as if an entirely new driver of innovation appears with the first humans. A driver even more powerful than natural selection. We call it collective learning. Here's how it works. We humans are very brainy. Look at that huge bulge at the front of your forehead. Still, we're not really that much brainier than other large mammals, such as chimps or dolphins. The crucial difference is human language. Which magnifies our brain inners by linking millions of individual brains into a single, collective brain that collects, processes, and accumulates new information generation by generation. Human language makes this possible because it's more precise, more powerful, and has more bandwidth from the languages of other animals. Unlike the languages of chimps or dolphins, human languages can describe abstract ideas such as innovation or pink elephants or the law of gravity. Or the rogue lion hanging out around the water hole the other side of the mountain. So please don't go there kids. Grammar multiplies the power of human language by letting us rearrange ideas in different configurations as in, the lion ate Fred. Or the much less likely, Fred ate the lion. The power of human language means that if I have a good idea I can pass it on. That's exactly what I'm trying to do right now, even if it's complex and abstract. I could explain where there's a water hole without physically taking you there. No chimp could do that. Now take thousands or millions of individuals, each one adding an idea or two. Put all the ideas together, rearrange them in new patterns, wait a few hundred generations and the possibilities for innovation begin to seem limitless. This is the power of collective learning. In a classic history of human technology called The Nature of Technology, Brian Arthur shows how technologies from stone tools to textiles to sailing ships and jet engines evolved by the addition of millions of small innovations to the collective pool of knowledge. By linking millions of brains across generations, human language has created a sort of collective transgenerational intelligence, whose knowledge can increase generation by generation. And that is transformative. Because a species with more knowledge is a species with more ability to exploit its environment. Collective learning over almost 200,000 years explains why today we humans have become the first single species in 4 billion years to dominate the biosphere. Innovation through collective learning began with the very first humans who appeared perhaps 200,000 years ago somewhere in Africa. They were foragers, that meant they lived in many ways, rather like many other large mammals. The difference was that ideas and innovations accumulated through collective learning. And as a result, our ancestors foraged with more and more expertise. They learned how to make more precise stone tools, to attach them to handles, to hunt so effectively that in some regions they drove large species, such as mammoths or giant kangaroos to extinction. They learnt new varieties of plants for food or medicine. To sew skin clothes so they could survive in cold climates. Innovation also shows up in ritual activity, and in works of art. Such as the astonishing cave paintings found from Europe to Australia. Our ancestors also migrated into new regions where you had to innovate in order to survive. The first Australians had to learn very fast, how to use entirely new plants and organisms. And the first Siberians had to learn very fast, how to live in tundra environments, hunt mammoths, and build warm dwellings, during the cold Siberian winters. By the end of the last ice age, about 10,000 years ago, a constant trickle of innovations had allowed humans to settle a huge variety of different environments in every continent apart from Antarctica. Then quite suddenly, at the end of the last Ice Age, we see a whole suite of new innovations that pop up in many different parts of the world and give humans much more control over resources. This is agriculture. Farmers manipulated their surroundings by removing trees or diverting rivers or disturbing the topsoil so as to increase the production of those plants and animals that they could use, such as wheat or cattle. And to get rid of those they couldn't use. In this way, agriculture gave our ancestors access to more and more of the energy and resources flowing through our biosphere. Not surprisingly, human populations began to rise and fast. Larger communities needed new institutions, new forms of control and governance. But more people meant more ideas being exchanged over larger areas. And as societies became more diverse, the ideas too became more varied and innovation accelerated. Innovation seems to ooze out of us humans uncontrollably. Today, Moore's Law tells us that in many areas, the rate of innovation is accelerating. But something like Moore's Law seems to have been at work throughout human history. [MUSIC]