Over the past 10,000 years, natural selection has contributed to the evolution of nearly 500 genes in the DNA of West Eurasians, affecting their looks and susceptibility to different illnesses, a new study finds.

Natural selection in this group led to an increased frequency of light skin tone, red hair, and resistance to HIV and leprosy (also called Hansen's disease), and it decreased the frequency of male-pattern baldness and rheumatoid arthritis susceptibility, the new study of 16,000 genomes reveals. This discovery contradicts the long-standing view that recent human evolution was limited.