Classification of Organisms

1
Classification of Organisms
Chapter 14

• Section 1 Categories of Biological
  Classification
• Section 2 How Biologists Classify Organisms

2
Taxonomy

• Taxonomy is the science of naming and classifying
  organisms
• Binomial nomenclature- Linnaeus 2 word system
  (Genus species)
• Scientific name
• honey bee
• Apis mellifera

3
Scientific Name

• 1st letter of Genus is capitalized
• 1st letter of species is lower case
• Name is usually written in italics
• Red Oak Quercus rubra

4
Classifying Organisms

• 3 Domains (new ??)
• Prokaryotes - Archaea
• Bacteria
• Eukaryotes - Protist, Fungi, Plants, Animals
• Levels of Classification Domain, Kingdom, Phylum,
  Class, Order, Family, Genus, Species

5
What is a Species?

• Biological species - a group of natural
  populations that are interbreeding or that could
  interbreed and are reproductively isolated from
  other such groups (natural barriers - geography)

6
of Species

• Some groups of species do not have barriers and
  can reproduce unlimitedly
• 1.5 million species identified in world today
• 5-10 million more are believed to be in the
  tropics alone (rainforests)
• New species identified regularly

7
Evolutionary History

• Phylogeny- system of classification based on
  similarities (evolutionary history)
• Convergent evol. Species evolve independently of
  one another, but have similarities due to similar
  habitat.
• Analogous characters- similarities that arise
  through convergent evolution

8
Evolutionary Systematics

• Claudistics- focus on sets of unique traits found
  in a group of organisms
• Phylogenic Tree- represents a hypothesis of
  evolutionary history that may be inferred b/c it
  wasnt observed