Mutation is simply defined as “random changes in genetic material”. Without mutations and there would be very little change in species or evolution. Humans inherit more than three times as many mutations from their fathers as from their mothers, and mutation rates increase with the father’s age but not the mother’s, researchers have recently found in the largest study of human genetic mutations to date. The study, based on the DNA of around 85,000 Icelanders, also calculates the rate of human mutation at high resolution, providing estimates of when human ancestors diverged from nonhuman primates. It is one of two papers published this week by the journal Nature Genetics as well as one published at Nature that shed dramatic new light on human evolution.