Final answer:
The basic characteristics of civilizations include advanced cities and technologies, complex institutions, and a system of record keeping. Civilizations emerged where sustainable agriculture was possible, leading to settled societies with organized governments and social structures.
Step-by-step explanation:
Historians have identified the basic characteristics of civilizations as advanced cities and technologies, complex institutions such as government and militaries, and a system of record keeping such as a written language. Early civilizations typically emerged around fertile river valleys, where they developed sustainable agriculture that supported a settled lifestyle. This, in turn, led to the rise of complex societies with features such as a government, division of labor, and social stratification. The ancient civilizations of Africa, Europe, Asia, and the Americas exemplified these trends by building impressive structures, forming organized governments, and developing unique cultural expressions and innovations.