When Melinda and I went on our spring vacation, I encouraged her to pack a copy of Yuval Noah Harari’s Sapiens: A Brief History of Humankind. I had just finished the book and I was dying to talk to her about it. It’s so provocative and raises so many questions about human history that I knew it would spark great conversations around the dinner table. It didn’t disappoint. In fact, in the weeks since we’ve been back from our holiday, we still talk about Sapiens.

Harari, who is an Israeli historian, takes on a daunting challenge: to tell the entire history of us, the human race, in a mere 400 pages. I’ve always been a fan of writers who try to connect the dots and make sense of the sweep of history. Probably no one has done it better than David Christian in his Big History lectures, which distill 13.7 billion years of history, from the Big Bang on, into a manageable framework that spans biology, physics, humanities, and the social sciences. While Harari concerns himself with a shorter time frame, the last 70,000 years of human history, his job is no less difficult. He sets out to explain how we, Homo sapiens (Latin for “wise person”), came to dominate the Earth and what may lie ahead for our species. 

Most humans assume that we were always the ones in charge, lording over the rest of the animals. But Harari reminds us that long before we built the pyramids, wrote symphonies, or walked on the moon, there was nothing special about us. “The most important thing to know about prehistoric humans,” Harari writes, “is that they were insignificant animals with no more impact on their environment than gorillas, fireflies or jellyfish.”  

One hundred thousand years ago, Homo sapiens was just one of a number of different human species, all competing for supremacy. Just as today we see different species of bears or pigs, there were different species of humans. While our own ancestors lived mainly in East Africa, our relatives Homo neanderthalensis, better known as Neanderthals, inhabited Europe. Another species, Homo erectus, populated Asia, and the island of Java was home to Homo soloensis. 

Each species adapted to its own environment. Some were big, fearsome hunters, while others were dwarf-like plant gatherers. As different as each species may have been, there is evidence of interbreeding among them. Scientists mapping the Neanderthal genome, for example, discovered that people of European origin today have a small percentage of genes from their Neanderthal ancestors. (That will make an interesting addition to many family trees!) ...