Anna Hartz
Crops did not just change farming and trade.
Food has shaped human history in more ways than most people realize. Over thousands of years, they may also have changed the human body itself. A new study now suggests that potatoes may have played an important role in human evolution in the Andes Mountains.
The starch gene
Researchers studied DNA from 3,723 people across 85 population groups around the world. They discovered that Quechua people from the Peruvian highlands often carry extra copies of a gene linked to starch digestion, according to Videnskab.
The gene is called AMY1. Nearly all humans have it. It helps the body produce amylase, an enzyme found in saliva that starts breaking down starch as soon as food enters the mouth.
Starch is a type of carbohydrate found in foods such as potatoes, rice, bread, and pasta. Amylase helps turn that starch into sugar that the body can use for energy.
The researchers found that people around the world usually had about seven copies of the AMY1 gene. But among the Quechua groups in Peru, the average was around ten copies.
Scientists believe this difference may be connected to the long history of potato farming in the Andes. People in the region began growing potatoes between 6,000 and 10,000 years ago. Using genetic dating methods, the research team found that the number of AMY1 copies started increasing during roughly the same period.
An advantage
The extra gene copies may have given people a small advantage. Those who could digest starch more efficiently may have had better access to energy from potatoes, which were a major part of the local diet.
Researchers say the effect would have been gradual. The advantage may have been tiny from one generation to the next. But over thousands of years, those extra gene copies became more common in the population.
The team also compared the results with groups of Maya ancestry from Central America. These populations also had long farming traditions, but they did not share the same deep connection to potato cultivation. They also did not show the same high number of AMY1 copies.
For the scientists, this strengthens the idea that potatoes helped shape the genetic development of people living in the Andes. A simple crop may have quietly influenced human biology over thousands of years.
