Final answer:
Surplus food resulted in specialization of labor and the division of tasks in early civilizations, leading to the development of skilled trades, social classes, and writing.
Step-by-step explanation:
The characteristic of civilization that immediately developed because of surplus food is specialization of labor. When agriculture produced more food than what was immediately necessary for survival, not everyone had to engage in food production. This led to a division of labor, where individuals could perform specific tasks such as crafts, building, or trade. Consequently, as some people focused on agriculture, others could devote time to developing new skills and technologies, like writing, which emerged from economic necessities related to tracking and managing agricultural products.
Cities began to form as agricultural surpluses supported larger populations. The creation of large-scale architecture and the stratification of social classes were also direct results of having a well-fed society. The ability to produce excess food meant that not all inhabitants of a civilization needed to farm, allowing for the emergence of different roles within the society, leading to the complex social structures characteristic of early civilizations.