Answer:The surpluses of food encouraged local and long-distance trade because they provided the people with a valuable trading good for which they were able to get other goods that they needed and desired.
Explanation:
The surpluses of food only occurred when the people started to engage into large scale agriculture. As they were able to satisfy their own demand for food, all of the rest of the food that was produced became a trading good. The people that were able to produce surpluses of food had big advantage because lot of people living in harsher regions were not able to do so.
The people that were not able to produce large quantities of food needed the surplus food from the people that were producing it. In order to get it without engaging in war though, they had to offer something in return. Very often they had goods that were attractive to the people that produced surpluses of food, goods like salt, gold, metals. This contributed to development of trade, both of short and longer distance, depending on what each trading side wanted to gain.
Regions that were able to produce surpluses of food were:
Mesopotamia
Egypt
Indus Valley
China
Regions that were not able to produce surpluses of food but were able to offer other goods were:
Anatolia
Central Asia
the Sahel
