Sapiens: A Brief History of Humankind

Homo sapiens developed language during the Cognitive Revolution, and it allowed them to communicate at a new level and in new ways. Homo sapiens acquired the ability to talk about things they could not see but only imagine, such as fantasy, myth, and religion. They could tell stories, conjecture, and collaborate with large numbers of other Homo sapiens. This ability set them apart from all other species and allowed information to pass between them in very detailed ways.

Animals like humans, such as chimpanzees, cannot form cooperative groups larger than about 50 animals. Humans can manage a personal network of around 150 other humans. When the group becomes larger, personal communication and gossip cannot be relied on to get everyone working together toward a common goal. Larger numbers need a shared belief system to collaborate without constant one-on-one communication.

Communication in large numbers is possible because of social constructs or shared myths and beliefs, called imagined realities in academic circles. Since the Cognitive Revolution, humans have been able to live not only in their present physical reality but also in imagined reality. People can now cooperate by changing the myth, the story, the belief, and therefore the imagined reality. These realities are not genetically based and so can change as beliefs change or when one human wants to convince others of a new idea. While a shared imagined reality allows humans to make laws for the sake of protection and safety when living together in large groups, this same reality can be used as reasoning to fight wars with other groups or to conduct trade with them. 

There is very little information available regarding prehistoric religion and beliefs. Differences in climate, location, and habitat meant there was not a single way of life, but instead many, for humans during and before the Agricultural Revolution. Ancient human groups lived in close contact with each other and had little privacy. Dogs were the first animals domesticated by ancient humans about 15,000 years ago.

Much of our behavior and psychology stems from human development during the period before the Agricultural Revolution, or about 10,000 years ago. One example is our genetic instinct to gorge on high-calorie food when more nutritious options are readily available. Humans of the time had much more knowledge and understanding of their natural physical world and surroundings than we tend to now. Each person had to know the many skills necessary for survival, including making tools, preparing and repairing materials for clothing, and maintaining shelter. Modern humans are far more specialized in their individual knowledge than were ancient humans, and today each of us is reliant on the collective knowledge of other humans for acquiring food, making our clothing, and building our homes.

Barring a few islands accessed by swimming or rafting across short stretches of water, all humans lived on the Afro-Asian landmass prior to the Cognitive Revolution. Humans’ invasion of Australia, about 45,000 years ago, and later of America, about 16,000 years ago via the Siberian peninsula, were the most important and devastating events in history. Humans were responsible for the unprecedented extinction of megafauna on these continents. Outer islands that escaped the notice of humans for a while longer, such as the Galápagos Islands, which were not inhabited by humans until the 19th century, retained their unique animal species.

The First Wave Extinction, which accompanied the spread of the foragers, and the Second Wave Extinction, which accompanied the spread of the farmers, shed light on the Third Wave Extinction of which we are a part. The Third Wave is fueled by today’s industrial activity. Homo sapiens have never lived in harmony with nature and are responsible for driving most plant and animal species to extinction. The only survivors will be humans themselves and the domesticated farm animals used for meat, wool, and leather.