If you find it difficult to resist the temptation of bread, noodles, or rice, then you may be able to shift some of the blame onto your ancient ancestors. Because a recent study published in Science has revealed an interesting fact: the human desire for carbohydrates may be deeply rooted in our genes, especially the salivary amylase gene (AMY1). Imagine that about 800000 years ago, much earlier than the emergence of agriculture, a small gene replication event quietly occurred, like a stone thrown into a calm pond, causing ripples. This' stone 'is the first replication of the salivary amylase gene, which gave early humans the ability to more efficiently break down starch in food. A study led by the University of Buffalo and the Jackson Laboratory in the United States utilized advanced genomic technologies such as optical mapping and long read sequencing to uncover a corner of this ancient story. The core content of the story tells the story of a key gene that exists in the human mouth and can break down complex carbohydrates such as rice, bread, and noodles. Its number of copies began to increase over 800000 years ago. And it is the replication of the AMY1 gene that lays the foundation for the human body to digest a large amount of starchy foods. Researchers analyzed the genomes of 68 ancient humans, including Neanderthals and Denisovans, and found that hunters at the time already had 4 to 8 copies of the AMY1 gene. This means that before we started planting wheat and rice, the human body was actually preparing for the upcoming 'starch feast'. When agriculture emerged, those who carried more copies of the AMY1 gene were better able to adapt to new dietary patterns. They not only digested starchy foods more effectively, but may also have stronger bodies to reproduce as a result. As a result, the descendants of these people gradually became a major part of society, and their genetic traits were widely spread. It is interesting that not only humans, but also domesticated animals that have co evolved with us, such as dogs and pigs, have more copies of the AMY1 gene due to sharing a starchy diet with humans. This is like a carefully designed dance by nature, allowing us to enjoy delicious food with our pet companions while also promoting each other's survival and development. Now, as we stand in the supermarket struggling to decide whether to buy a delicious bag of bread, let's think about the millions of years of evolution hidden behind it. We can thank those ancient genes, which not only helped our ancestors through difficult times, but also gave modern life a unique flavor. The next time you can't resist eating that sweet bread, maybe you can tell yourself, 'My genes make me do this!'