The exchanging of goods, plants and animals from New World to Old is called Columbian Exchange.
With the discovery of America by Christopher Columbus in 1492, led the beginning of the Columbian Exchange. The European not only traded goods but brought diseases in the New World. Native Americans were affected the most by the exchange. The spread of diseases surprised because it finished almost all the early civilization in America. The Native American died with chickenpox, smallpox, malaria, cholera, measles, and scarlet fever.
The answer is oral.
These were passed down through stories made by wise men or elders of a
village or tribe from generation to generation.
It was probably a strict process as each successor knew the history of
his clan for he was a source of knowledge to those around him.
