2. Why Do We Classify Organisms?
Biologists group organisms to represent
similarities and proposed relationships.
Classification systems change with
expanding knowledge about new and
well-known organisms.
Tacitus bellus
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3. Leucaena leucocephala
Lead tree
Classification
Binomial Nomenclature
Two part name (Genus, species)
Hierarchical Classification
Seven Taxonomic Catagroies
Systematics
Study of the evolution of biological diversity
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4. Carolus von Linnaeus
(1707-1778)
Swedish scientist who laid
the foundation for modern
taxonomy
Binomial Nomenclature
Carolus von Linnaeus
Two-word naming system
Genus
Noun, Capitalized,
Underlined or Italicized
Species
Descriptive, Lower Case,
Underlined or Italicized
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5. Hierarchical Classification
Taxonomic categories
Kingdom King
Phylum Philip
Class Came
Order Over
Family For
Genus Green
Species Soup
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6. Kingdoms and Domains
Bacteria Archaea Eukarya
Bacteria Archaea Protista Plantae Fungi Animalia
Monera Protista Plantae Fungi Animalia
The three-domain system
The six-kingdom system
The traditional five-kingdom system
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7. Systematics:
Evolutionary Classification of Organisms
Systematics is the study of the evolution of biological
diversity, and combines data from the following areas.
Fossil record
Comparative homologies
Cladistics
Comparative sequencing of DNA/RNA among
organisms
Molecular clocks
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8. Taxonomic Diagrams
Mammals Turtles Lizards and
Snakes
Crocodiles Birds Mammals Turtles Lizards and
Snakes
Crocodiles Birds
Cladogram
Phylogenetic
Tree
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9. Dichotomous Keys Identify Organisms
Dichotomous keys versus evolutionary classification
Dichotomous keys contain pairs of contrasting
descriptions.
After each description, the key directs the user to
another pair of descriptions or identifies the organism.
Example:
1. a) Is the leaf simple? Go to 2
b) Is the leaf compound? Go to 3
2. a) Are margins of the leaf jagged? Go to 4
b) Are margins of the leaf smooth? Go to 5
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10. Thank You
This concludes a brief review of biological
classification.
You may find additional information on this section of
in the expanded content talks and in the notes below
each slide in the slide library.
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