Viruses are dominant driver of human evolution, researchers say

In a new study published in the journal eLife, scientists apply big-data analysis to reveal the full extent of viruses’ impact on the evolution of humans and other mammals. Their findings suggest 30% of all protein adaptations since humans’ divergence with chimpanzees have been driven by viruses. When an environmental change occurs, species are able to adapt in response due to mutations in their DNA. Although these mutations occur randomly, by chance some of them make the organism better suited to their new environment. These are known as adaptive mutations. In the past decade, scientists have discovered a large number of adaptive mutations in a wide variety of locations in the genome of humans and other mammals. The fact that adaptive mutations are so pervasive is puzzling. What kind of environmental pressure could possibly drive so much adaptation in so many parts of the genome? Viruses are ideal suspects since they are always present,...