Lesson 5

• Classification of Taxonomy

  • Description
  • Identification
  • Nomenclature
  • Classification
• Taxonomic Classification

  • Hierarchy - classification of group organisms according to their relatedness. They are classified based on hierarchy.
• Taxonomic traits

  • characters are used to classify organisms according to their taxonomic groups.
  • Important in quantifying the degree of relatedness of species with one another.
• Categories of Taxonomic Characters

  • Ancestral Traits - homologous within groups of organisms.
  • Derived Traits - characters that are present in species but absent in their ancestors; or vice versa.
• Taxonomic Evidence for Classification

  • Morphological
  • Developmental
  • Physiological
  • Genetic
• Morphological Traits

  • set of physical features of living organisms.
  • It can be external or internal morphological features that are used for the classification.
• Developmental Traits

  • A set of developmental features that can be used for classification.
  • These are characteristics that can be observed in living organisms during stages of their embryonic development.
• Psychological Traits

  • It mainly focuses on the functional features of the structures.
  • These traits are usually observed as they can be useful in constructing convergent evolutionary parts among distantly related organisms.
• Genetic Traits

  • It refers to the specific sequences of the DNA molecule in organisms.
  • These traits are highly useful in delineating organisms until the species or even until the sub-species level.
• Use of Traits in Classification

  • Different traits are used to properly classify organisms.
  • Both morphological and genetic features must always go parallel with one another.
• Taxonomy

  • refers to the science of describing and classifying organisms.
  • It takes into account how organisms are related, but it does not reflect evolutionary relationships.
• Taxonomic Evidence

  A) Taxonomic Classification

  B) Morphology

  C) Physiology

  D) Genetics

  E) Anatomical Homology

  F) Developmental Homology

  G) Analogous Structure

  H) DNA Sequence