Other Religions Atheism and Agnosticism Is There Direct Evidence of Evolution? How Genetics and Observation Provide Evidence for Evolution, Common Descent Share Flipboard Email Print Other Religions Belief Systems Atheism and Agnosticism Logic Ethics Key Figures in Atheism Evolution Atheism Myths and Misconceptions By Austin Cline Atheism Expert M.A., Princeton University B.A., University of Pennsylvania Austin Cline, a former regional director for the Council for Secular Humanism, writes and lectures extensively about atheism and agnosticism. our editorial process Austin Cline Updated March 06, 2017 The direct evidence for common descent and evolution are enabling evidence. They demonstrate that common descent is possible and maybe even likely. However, they don't conclusively show that common descent occurred because no one was there to observe it over such a long period of time (the same problem that exists when there is no direct eyewitness in a murder trial). We'll explain how genetics and observation provide evidence for evolution. Direct Evidence and Evolution p.folk/photography/Moment/Getty Images The direct evidence for common descent supports evolution because: we understand the basic mechanisms by which change occurswe have seen changes occurthere is no known reason why large-scale changes can't occur over successive generationsthere have been billions of years for evolution to workthere has been a huge number of organisms on which evolution could operate Given these facts, it is reasonable to conclude that evolution has occurred. If you consider the fluidity of species demonstrated by ring species, natural selection, and the likelihood of many environmental changes over time, it becomes even more probable that large-scale evolution has occurred. How Genetic Mutations Drive Evolution The basic definition of evolution is a change in the gene pool of a population of organisms over time. All of evolution is based on genetic change. Scientists still have a lot to learn about the workings of genetic code, but science has built up a large volume of knowledge about how the genetic material of living organisms works. We have a pretty good understanding of what DNA does in general and, equally important to evolution, how DNA changes. Observing Evolution - How Evolution Has Been Observed The most basic direct evidence of evolution is our direct observation of evolution occurring. Creationists claim that evolution has never been observed when, in fact, it's been observed both in the lab and the field repeatedly.