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10.3: Understanding phylogenetic trees

  • Page ID
    49714
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    1. Phylogenetic tree is a dichotomously branching diagram where all terminals (tips representing objects) are connected. Phylogenetic tree is related with time; start of the diagram is always older then end. All terminals must be labeled. Nodes which have more than two branches are typically not allowed.

    2. Tree edges may be freely rotated in any direction. For example, these trees are same:

    10.3.1.PNG
    Figure \(\PageIndex{1}\)
    1. Direction of branches also does not matter. These trees are same:

    10.3.2.PNG
    Figure \(\PageIndex{2}\)
    1. Apomorphies (and reversals) could be shown as edge labels:

      10.3.3.PNG
      Figure \(\PageIndex{3}\)
    2. Phylogenetic tree is directly related with taxonomy (classification):

      • Suborder Strepsirrhini: lemur

      • Suborder Haplorrhini:

        • Superfamily Cercopithecoidea: baboon

        • Superfamily Hominoidea:

          • Genus Pan: chimpanzee

          • Genus Homo: human


    This page titled 10.3: Understanding phylogenetic trees is shared under a Public Domain license and was authored, remixed, and/or curated by Alexey Shipunov.

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