It’s been said that if a machine ever gains awareness, it will be not due to our careful programming, but to an unforeseeable anomaly. Perhaps the first anomaly occurred back in the distant primordial fog of human evolution. We may never know. But a new analysis of ancient genomes suggests that different branches of the human family tree interbred multiple times, and that some humans carry DNA from an archaic, unknown ancestor.
From about two million years ago until around 10,000 years ago, the world was inhabited, at one and the same time, by several human species, one of the earliest being Homo erectus, who walked upright and were built like modern humans, and they eventually spread from Africa, across Europe and Asia. Our possible direct ancestor, Homo erectus, researchers have discovered, crafted a cutting-edge tool out of a hippo’s leg bone around 1.4 million years ago in the early Acheulean, starting our immense journey from ax to algorithms and perhaps Homo sapiens last great invention, artificial intelligence.