What we know about human history is only a fraction of the full story. Much of the rest is like dark matter, invisible to us. We can’t see it, and we can only see the effects of its presence. But thanks to new techniques for DNA sequencing, dating ancient detritus, mathematical models, and aerial and lidar archaeology, we are now able to get a faint idea of what this world might have looked and felt like. Who was the first human? Where did the first civilization begin and what did life look like back then?