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9.5: Key Points

  • Page ID
    47811
    • Callan Bentley, Karen Layou, Russ Kohrs, Shelley Jaye, Matt Affolter, and Brian Ricketts
    • OpenGeology

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    1. Evolution results from the mutation of genetic material and the subsequent accumulation of changes in DNA through many generations of offspring.
    2. Evolution represents a coherent view of life and is built upon a foundation of evidence from the fossil record, biochemistry, observations of naturalists, and observations still being made in labs, in nature and on other planets.
    3. Carl von Linne introduced binomial nomenclature to create a simple taxonomy in which organisms were classified in a nested hierarchy with Kingdoms at the highest rank and then divided into “Phyla,” then “Classes,” “Orders,” “Families,” “Genera,” and finally “Species.”
    4. Early evolutionary theory introduced natural selection, the process by which species change over time as organisms with enough favorable characteristics survive long enough to pass on their genes.
    5. Understanding how natural selection worked relied on the understanding of how genes were passed down from parents to offspring and how certain traits are passed on or expressed.
    6. Several key processes drive evolutionary change: genetic mutation, gene migration, genetic drift, horizontal gene transfer, and natural selection.
    7. Sexual selection involves species preferentially having their genetic material passed on due to having more desirable physical features.
    8. Artificial selection is controlled by humans as we manipulate what genes are passed down from one generation to another such that the species evolves to have favorable traits.
    9. Early on, fossils were not though of as evidence of past life but eventually they were accepted as evidence of ancient life.
    10. By studying fossils early on, the concept of extinction was introduced.
    11. Once the ages of various fossils were established, scientists concluded the age of the rock containing the fossil had to be the same age as the fossil itself.
    12. Transitional fossils show the link between two major groups as they have traits of the ancestral and descendant groups.
    13. Extinction of species is important to evolutionary theory as it makes space for other species to evolve into.
    14. Mass extinctions occur as a large number of the species on Earth die off. There are five widely accepted mass extinction events: the end of the Ordovician Period, the end of the Devonian Period, the end of the Permian Period, the end of the Triassic Period, and the end of the Cretaceous Period

    This page titled 9.5: Key Points is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Callan Bentley, Karen Layou, Russ Kohrs, Shelley Jaye, Matt Affolter, and Brian Ricketts (OpenGeology) via source content that was edited to the style and standards of the LibreTexts platform.