Biology  5/e   Raven/Johnson
	Student   Online Learning Center

Nature documentaries and stories about "Mother Nature" are filled with examples of remarkable adaptations exhibited by plants and animals. The adaptations help the organisms survive in harsh and unusual environments, such as polar bears in the arctic or cacti in the desert. These adaptations are the result of natural selection and evolutionary change. We are surrounded by evidence that evolution has occurred in the past and is continuing to occur. The diversity of life that exists on earth today, plus all the vast and minute specializations that it displays, is the result of the action of natural selection and evolution. As discussed in this chapter, in some cases we have even been able to identify particular selection forces and observe their impacts on populations. Despite the overwhelming evidence supporting evolutionary theory, some people continue to confuse science and religion, and try to promote religious beliefs as scientific theory. Although there may be debate among scientists about specific details of the theory (e.g., about the rates of evolutionary change), there is virtually no disagreement that evolution is the best scientific theory explaining the origin of species.

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