によって yasmine sabri 17年前.
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Mechanisms of Evolution
The process of evolution encompasses several mechanisms that contribute to the diversity and complexity of life on Earth. Adaptation through natural selection allows organisms to become well-suited to their environments, while vestigial structures serve as evidence of non-adaptive traits.
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Mechanisms of Evolution Religion and science are very different things In religion, beleifs are beyond the natural world In science only natural causes are used to explain natural phenomena Causes of mutations External influences. e.g. exposure to specific chemicals or radiation DNA fails to copy accurately Evolution is not a ladder of progress Adaptation Non-adaptation: Vestigial structures Well fitted to thei function and produced by natural selection Feature common in populations that provides improved functions Evolution is both observable and testable Genetic mutation Artifical seletion in laborotary Study of living species , e.g Darwin's finches Fossil record Biological Evolution Large-scale:desent of different species from one common ancestor over generations Small-scale:changes in gene frequency from one generation to another Descent with modification Life on earth shares a common ancestor Natural Selection Continuation for the best adaptest Heredity Differential reproduction Variation in traits Sources of Genetic variation Sex Can intoduce new gene combinations into populations Gene Flow Movement of genes from one population to another Mutations Evoultion is based n the accumlation of many mutations Is change in DNA Artifical Selection People instead of nature select organisms to reproduce Farmers and Breeders Evoultion in the farm stock Plants and animals with desirable characterisics to reproduce
