Classifying Organisms

1
Classifying Organisms

• Read Pg 300-315
• Pg 304 1-2
• Pg 312 1-2

2
Taxonomy

• A field of biology dedicated to identifying and
  classifying organisms.
• Determines relationships based on evolutionary
  traits.
• Uses a phylogenetic tree to display information
  on linked organisms.

3
KPCOFGS

• Most common classification system based on Carl
  von Linné.
• Uses 5 levels
• Kingdom- most broad
• Phylum
• Class
• Order
• Family
• Genus/Genera (like a genre of books!)
• Species- most specific

4
Tweaks

• Linnés model only had 2 kingdoms Plants and
  Animals
• Plantae- Multicellular autotroph eukaryotes
• Animalia- Multicellular heterotroph eukaryotes
• Since then, 3(ish) more have been added
• Protista- unicellular and multicellular
  eukaryotes
• Monera- unicellular prokaryotes
• Fungi- heterotroph eukaryotes (not plants!)
• Virus- undecided

5
Scientific naming

• When we classify an organism, we can trace its
  name through each level of the phylogenetic tree.
• We usually only refer to an organism by its
  GENUS and SPECIES (binomial nomenclature)
• The genus is capitalized and species is not
• Both genus and species are italicized.
• Ex Cambarus bartoni
• The trouble with common names is that one
  organism may have multiple names or different
  organisms share a similar name
• Ex Crawdad, crayfish, mudbug OR Black bear and
  Koala bear

6
Problems in classification

• Some organisms share physical traits that
  mismatch fossil records
• Evolutionary records show uniquely separate
  organisms developing similar physical traits

7
What kind of traits do we look at?

• When we discover new organisms we look at a
  variety of characteristics
• How do they supply their cells with nutrients?
• How do they perform gas exchange?
• How do they remove waste?
• How do they intake nutrients?
• How do they move and interact with their
  environment?

8
As we look

• For the next many weeks, we will learn about many
  types of organisms
• It is important to answer these questions to
  discover differences between the branches of a
  phylogenetic tree.

9
Classifying

• As we move through the phylogenetic tree, try and
  identify the milestones (or major physical
  traits) that create the branches of the tree.

10
Activity

• Write down a list of 20 animals.
• Complete the handout phylogenetic tree.
• What traits separate organisms from one another?
• Use your understanding of classifications to
  organize your 20 animals into a tree.