Since the early beginnings of farming, humans have used natural practices such as cross-breeding plants to find the best produce for consumption and growing. These practices change the size, color, and amount of seeds in a fruit, among other characteristics.
In the 1970s, however, scientists began genetically modifying foods to make the changes more predictable and favorable. The first genetically modified organism, or GMO, produce available for purchase was a tomato in 1994. Now, GMO crops are grown in 24 countries and imported and sold in 43.