Answer:
Food surpluses affected the people and populations because the availability of surplus food means an individual will most likely have more children. This is because food is needed for survival and having it excess can also help in providing more money and other resources.
Increase in population helped and allowed the ancient civilizations to grow and prosper as a result of the increase in the population helping in different areas of the economy of the country. This caused a ripple effect by increasing trade between countries which also had a positive effect on the civilization process.