The central ideas of evolution are that life has a history — it has changed over time — and that different species share common ancestors

how these trees are constructed, and how this knowledge affects biological classification. You will also find a timeline of evolutionary history and information on some specific events in the history of life: human evolution and the origin of life.

Evolution is the process by which modern organisms have descended from ancient ancestors. Evolution is responsible for both the remarkable similarities we see across all life and the amazing diversity of that life

Descent and the genetic differences that are heritable and passed on to the next generation; Mutation, migration (gene flow), genetic drift, and natural selection as mechanisms of change; The importance of genetic variation; The random nature of genetic drift and the effects of a reduction in genetic variation; How variation, differential reproduction, and heredity result in evolution by natural selection; and How different species can affect each other's evolution through coevolution.