Final answer:
Hunter-gatherers were nomadic due to the need to follow seasonal food sources and to avoid resource depletion. Their mobility was necessary for survival, making sedentary life impractical until the domestication of plants and animals allowed for stable food supplies.
Step-by-step explanation:
Hunter-gatherer societies did not live in one place due to the need to follow animal herds and gather plants that were not available all year in a single location. Their survival depended on moving to where food was available, leading to a nomadic lifestyle. The hunter-gatherers moved as a response to the seasonal migrations of game, scarcity of resources, and sometimes conflict with other groups. These communities were often small and without a surplus of resources. They had to be mobile, carrying only what was necessary, making it impractical to settle in a single place. As they roamed vast areas, they connected different regions and cultures.
Before the domestication of plants and animals, there was insufficient food to sustain large, static populations. With no way to preserve or transport large amounts of food, and with each area having limited resources that would eventually be depleted, sedentary life was not feasible. The domestication of crops and livestock marked a significant change, enabling people to settle and form permanent communities that eventually developed into cities.