“Now ancient humans also had their special thing: they knew how to use stones to crack open bones so they could eat the marrow inside. Even more important, human learned that making tools is a good idea.”

Harari shows how humans began to distinguish themselves from other animals and entered the Stone Age. They first discovered that they could extract marrow from bones for substance using rocks to break them. This development was the first step toward the later development of stone tools, the first ancient technology. This passage is an example of the book’s chronological evolutionary structure.

“Once they started cooking, that all changed: Humans could spend far less energy chewing and digesting and had more energy to feed big brains.”

Harari argues that one of humanity’s first great discoveries was the ability to make fire. This passage shows how Harari identifies evolutionary shifts that have facilitated human creativity and ingenuity, allowing Sapiens to dominate the world. This is key for his book’s message that human success is the result of evolutionary processes outside moral prerogatives.

“For more than a million years, as humans adapted to unique conditions of each area, they gradually became more and more different.”

Harari uses evolutionary principles to explain why different categories of humans, such as the Floresians, Neanderthals, and Denisovans, existed in the prehistoric age. At that time, our species, Homo sapiens, was one variety of human among many, just as today there are many varieties of bears, birds, or cattle. This supports Harari’s message that Sapiens are not unique in their humanity through human history, challenging narratives of exceptionalism.