The Columbian exchange, also known as the Columbian interchange, named after Christopher Columbus, was the widespread transfer of plants, animals, culture, human populations, technology, diseases, and ideas between the Americas, the Old World, and West Africa in the 15th and 16th centuries. It also relates to European colonization and trade following Christopher Columbus's 1492 voyage. Invasive species, including communicable diseases, were a byproduct of the exchange. The changes in agriculture significantly altered global populations. The most significant immediate effects of the Columbian exchange were the cultural exchanges and the transfer of people (both free and enslaved) between continents.