Explain how vertical trade has the people in the andes to overcome the challenge of the mountains.

In a typical Andean market town, people from villages at different elevations meet to trade their cops. Because people grow crops suited to their own climate zone, they trade "up" and "down". Tropical foods such as bananas and sugar cane, grown in the tierra client, may be traded for the potatoes and cabbages that grown in the tierra fria. Village farmers, highland cheese makers coastal fishermen, and peddlers all meet in the Andean market town.

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