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1.5: Systematics

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    How can we best conserve plant biodiversity? Systematics, a combination of taxonomy and phylogenetics, is critically important in plant biology. It helps us to categorize plants and understand natural diversity. Each plant species has a common name and a scientific name. Scientific names are in Latin and binomial, as follows:

    Common name: Pea
    Scientific name: Pisum sativum
    Family: Fabaceae
    Class: Dicot
    Varieties: garden peas, snow peas, snap peas

    Systematics uses cladograms (mostly morphological characteristics) and phylogenetic trees (morphological plus genetic characteristics). Phylogenetic trees (a.k.a., evolutionary trees) are used in comparing plant species in evolutionary time and distance. Finally, two plant species are considered more related if the phylogenetic tree shows a more recent ancestor.

    \(\PageIndex{1}\). Student Learning Outcomes (SLOs)

    • SLO 05.01: Apply the best practices for learning systematics
    • SLO 05.02: Explain binomial system
    • SLO 05.03: Distinguish between phylogenetic trees and cladograms
    • SLO 05.04: Distinguish between homologous vs analogous characters
    • SLO 05.05: Identify given plant species with their scientific names based on their key features
    • SLO 05.06: Explain the differences between ancestral and derived features
    • SLO 05.07: Diagram a typical plant cladogram

    \(\PageIndex{2}\). Big Picture


    \(\PageIndex{3}\). Vocabulary and Key Concepts


    \(\PageIndex{4}\). Test Your Knowledge

    • Assessment 05.3.1: TRUE or FALSE: Carl Linnaeus first proposed the systematics.
    • Assessment 05.3.2: TRUE or FALSE: Clades arose before are named “basal”.
    • Assessment 05.3.3: Provide similarities between cladogram and phylogenetic tree.
    • Assessment 05.3.4: List specific characteristics of model plant Arabidopsis thaliana for plant biology.

    \(\PageIndex{5}\). Can You Spot These Plants?


    \(\PageIndex{6}\). Check Your Answers

    1. TRUE
    2. TRUE
    3. They are used interchangeably. While phylogenetic tree’s branch length may be considered important indicator of time / change, cladograms missing this
    4. Short generation time. Small genome and mapping completed. Availability of many variants. Easy to grow in the lab

    This page titled 1.5: Systematics is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by Gokhan Hacisalihoglu (Florida State Open Publishing) via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.