Final answer:
The shift from a hunter-gatherer to an agricultural lifestyle 10,000 years ago, driven by the need for a more reliable food source, enabled humans to settle in one place, leading to the development of permanent communities and cities.
Step-by-step explanation:
The cause of people having no choice but to stay in one place and survive off of plant life relates to the advent of agriculture approximately 10,000 years ago. Prior to this, humans were hunter-gatherers, following animal herds and gathering edible plants. This nomadic lifestyle was precarious, as it did not produce a significant food surplus, limiting population growth and the formation of settlements. However, a gradual shift towards farming allowed for the production of a reliable food source, enabling the formation of more permanent communities and eventually leading to specialized labor and the development of cities. Factors such as climate changes, resource scarcity, and ecological interdependencies also played crucial roles in this transition from a nomadic to a settled lifestyle, and not all societies adopted farming despite its advantages.