Mutations can be random (for example, when replicating cells make an error while copying DNA), or happen as a result of exposure to something in the environment, like harmful chemicals or radiation. The mutation of genes is an important source of genetic variation within a population. Mutations are changes in the structure of the molecules that make up genes, called DNA. He argued that natural selection explained how a wide variety of life forms developed over time from a single common ancestor.ĭarwin did not know that genes existed, but he could see that many traits are heritable-passed from parents to offspring. By choosing which pigeons mated with others, hobbyists created distinct pigeon breeds, with fancy feathers or acrobatic flight, that were different from wild pigeons.ĭarwin and other scientists of his day argued that a process much like artificial selection happened in nature, without any human intervention. He pointed to the pastime of pigeon breeding, a popular hobby in his day, as an example of artificial selection. It is one of the processes that drives evolution and helps to explain the diversity of life on Earth.ĭarwin chose the name natural selection to contrast with “artificial selection,” or selective breeding that is controlled by humans.
Natural selection can lead to speciation, where one species gives rise to a new and distinctly different species. Through this process of natural selection, favorable traits are transmitted through generations.
Over time, these advantageous traits become more common in the population. These individuals then pass the adaptive traits on to their offspring. Individuals with adaptive traits-traits that give them some advantage-are more likely to survive and reproduce. This variation means that some individuals have traits better suited to the environment than others. Individuals in a population are naturally variable, meaning that they are all different in some ways. Natural selection is the process through which populations of living organisms adapt and change. In 1859, he brought the idea of natural selection to the attention of the world in his best-selling book, On the Origin of Species.
English naturalist Charles Darwin developed the idea of natural selection after a five-year voyage to study plants, animals, and fossils in South America and on islands in the Pacific.
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