5.3 Classification of Biodiversity

Essential Idea

• Species are named and classified using an internationally agreed system.

Understandings

1. The binomial system of names for species is universal among biologists and has been agreed and developed at a series of congresses.

2. When species are discovered they are given scientific names using the binomial system.

3. Taxonomists classify species using a hierarchy of taxa.

4. All organisms are classified into three domains.

5. The principal taxa for classifying eukaryotes are kingdom, phylum, class, order, family, genus and species.

6. In a natural classification, the genus and accompanying higher taxa consist of all the species that have evolved from one common ancestral species.

7. Taxonomists sometimes reclassify groups of species when new evidence shows that a previous taxon contains species that have evolved from different ancestral species.

8. Natural classifications help in identification of species and allow the prediction of characteristics shared by species within a group.

Applications

1. Classification of one plant and one animal species from domain to species level.

2. Recognition features of bryophyta, filicinophyta, coniferophyta and angiospermophyta.

3. Recognition features of porifera, cnidaria, platyhelmintha, annelida, mollusca, arthropoda and chordata.

4. Recognition of features of birds, mammals, amphibians, reptiles and fish.

Skills

1. Construction of dichotomous keys for use in identifying specimens.

Guidance

• Archaea, eubacteria and eukaryote should be used for the three domains.

• Members of these domains should be referred to as archaeans, bacteria and eukaryotes.

• Students should know which plant phyla have vascular tissue, but other internal details are NOT required.

• Recognition features expected for the selected animal phyla are those that are most useful in distinguishing the groups from each other and full descriptions of the characteristics of each phylum are NOT needed.

• Viruses are NOT classified as living organisms.

Key Vocabulary

• Nomenclature

  • Binomial system

• Taxonomy (classifying organisms)

• Natural classification

  • Domains

    • Archaea

    • Eubacteria

    • Eukaryote

  • Kingdom

  • Phylum

    • Plantae

      • Bryophyta (non-vascular)

      • Filicinophyta

      • Coniferophyta

      • Angiospermophyta

    • Animalia

      • Porifera (sponges)

      • Cnideria (jellies)

      • Platyhelmintha (flatworms)

      • Annelida (segmented worms)

      • Mollusca (snails, clams, etc.)

      • Arthropoda (insects, crabs, etc.)

      • Chordata (vertebrates)

  • Class (of vertebrates)

    • Birds

    • Mammals

    • Amphibians

    • Reptiles

    • Fish

  • Order

  • Family

  • Genus

  • Species

Textbook Reading and/or Activities

Click HERE for a pdf of chapter 5.

• Pages 253-270

  • Nature of Science (p.253)

  • Challenge Yourself (p.259)

  • Worked Example (p.268-269)

  • Challenge Yourself (p.269)

  • TOK (p.269)

  • Exercises (p.270)

Notes and Study Questions

Bob Smullen Notes Study Questions

Jacob Cedarbaum Notes Study Questions

Stephen Taylor Notes Study Questions

Chris Paine Notes Study Questions

Learning Activities

Constructing a Dichotomous Key

This worksheet provides an opportunity to use and create a biological key, which can help identify an unknown (but previously discovered) species in the environment.

Supplemental Reading

Classification

This reading (about 20-30 mins) will help clarify the divisions of classification as well as providing distinguishing characteristics for the various phyla and classes identified in the Applications. Check out the two Test Bites on page 6.