Evolution, the change in allele frequency over time in a population of organisms is a fact and is only controversial among a vanishingly few ideologues and practically no scientists. The theory of evolution by natural selection is supported by over 95% of all scientists and is not controversial among the scientific community because it has been observed and tested for 150 years. There are some religious ideologues who can not accept the evidences that refute their creation story, so they make evolutionary theory only controversial politically.