Here in the Northern Hemisphere during these hot summer days, a lot of us are eating delicious produce like watermelon, peaches and corn-on-the cob. These days, there’s lots of chatter about GMO concerns (genetically modified organisms), but every species that’s ever been farmed by humans has been genetically modified over time as a result.
Let’s start with watermelon which has its origins around 3000 B.C. in Africa as a hard, bitter fruit the size of a walnut with hard, pale-green flesh. It caused inflammation and had a terrible bitter taste. Why grow more of these?? Water. Unlike other fruits, watermelons could remain edible for weeks or even months if kept in a cool shaded area and provide a source of water – small as it may be. Through thousands of years of artificial selection (unintentional genetic engineering), we have the modern watermelon that bears no resemblance to its African ancestor. Modern watermelons are sweeter, juicier, more colorful and easier to grow than their ancestral varieties.
Peaches used to be small, cherry-like fruits with little flesh. They were first domesticated around 4,000 BC by the ancient Chinese and tasted earthy and slightly salty. Farmers selected seeds from the tastiest fruits for re-planting and as they tended to the trees for thousands of years, the fruits became bigger and juicier with each generation. After 6,000 years of artificial selection, the resulting peach became 16 times larger, 27% juicier and 4% sweeter than its wild cousin, and had massive increases in nutrients essential for human survival as well.
Perhaps the most iconic example of selective breeding is North American sweetcorn. Some 9,000 years ago, corn as it is known today did not exist. Long ago in southwestern Mexico, locals encountered a wild grass called teosinte that offered ears smaller than a pinky finger with just a handful of stony kernels. Perhaps driven by necessity, Indigenous cultivators saw potential in the grain, adding it to their diets and putting it on a path to become a domesticated crop that now feeds billions. Today, corn is 1,000 times larger and much easier to grow and peel. 6.6 % of it is made up of sugar, compared with just 1.9 % in natural corn. Most changes towards modern corn occurred from the 15th century onwards, when European settlers started cultivating the crop.
Next time someone tells you we shouldn’t be eating food that’s been genetically modified, you can tell them we already are!