The era of foragers, also known as the “Paleolithic era” deals with the lives of hunter-gatherers, who had survived for over 240,000 years. Their nomadic lifestyles of traveling and hunting has created a huge impact to the environment and their sophisticated technology, such as sticks and stones allowed them to settle adaptively across the globe with different climates. Succeeding foraging is the agrarian era, that lasted for almost ten thousand years. In this era, advancement with agriculture and pastoralism were a necessity as it allowed cities, states, and empires to form. Complex societies, especially hierarchy, followed along. The modern era is described to be the fastest out of the three eras proved that tremendous in population, innovation, and productivity in less than a millennium was possible. The industrial revolution was the next level of domination after agriculture and since has shaped the world through today where better sophisticated technology (such as the steam engine that allowed quick supply of cheap energy) was able to expand to all regions. After the main text, this book ends with the resource pages, periodization chapter, and the index. (need…