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Biology LibreTexts

2.1: Systematics

  • Page ID
    41417
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    • 2.1.1: Introduction
      All life on Earth is related. This section explores how we determine and depict those relationships.
    • 2.1.2: Organizing Life on Earth
      In scientific terms, the evolutionary history and relationship of an organism or group of organisms is called phylogeny. Phylogeny describes the relationships of an organism, such as from which organisms it is thought to have evolved, to which species it is most closely related, and so forth. Phylogenetic relationships provide information on shared ancestry but not necessarily on how organisms are similar or different.
    • 2.1.3: Determining Evolutionary Relationships
      Scientists must collect accurate information that allows them to make evolutionary connections among organisms. Similar to detective work, scientists must use evidence to uncover the facts. In the case of phylogeny, evolutionary investigations focus on two types of evidence: morphologic (form and function) and genetic.
    • 2.1.4: Perspectives on the Phylogenetic Tree
      The concepts of phylogenetic modeling are constantly changing. It is one of the most dynamic fields of study in all of biology. Over the last several decades, new research has challenged scientists’ ideas about how organisms are related. New models of these relationships have been proposed for consideration by the scientific community.
    • 2.1.5: Chapter Summary
      A brief summary of the concepts covered in Chapter 2.1

    Contributors and Attributions

    • Chapter thumbnail by Pengo, Public domain, via Wikimedia Commons.

    This page titled 2.1: Systematics is shared under a CC BY-NC 4.0 license and was authored, remixed, and/or curated by Melissa Ha, Maria Morrow, & Kammy Algiers (ASCCC Open Educational Resources Initiative) .