Evolution

Evolution is a scientific theory used by biologists. It explains how living things change over a long time and how they have come to be the way they are. The earth has been around for a very long time. By doing research on the layers of rock, we can find out about its past. That kind of research is called historical geology. We know that living things have changed over time because we can see their remains in the rocks. These remains are called fossils. So we know that the animals and plants of today are different from those of long ago, and the further we go back, the more different the fossils are. How has this come about? That evolution has taken place is a fact because it is overwhelmingly supported by many lines of evidence. At the same time, evolutionary questions are still being actively researched by biologists. Comparison of DNA sequences allows organisms to be grouped by how similar their sequences are. In 2010, an analysis compared sequences to phylogenetic trees and supported the idea of common descent. There is now strong quantitative support for a formal test for the unity of life. The theory of evolution is the basis of modern biology. Nothing in biology makes sense except in the light of evolution.