Khan Academy Static

The invention of farming led to dramatic changes in the way humans got their food. By domesticating plants and animals, people could settle in one place. Because domestication gave people more control over the plants and animals in an area, human groups could grow bigger and denser. As these populations grew and turned into cities, states, and empires, greater opportunities for collective learning evolved but so did the types of challenges human communities had to face. Population growth, specialization of labor, and the emergence of rulers and social hierarchies all paved the way for increased collective learning, but they also created some complex problems and relationships that we are still struggling to resolve today.

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