1. Classification/Taxonomy
Chapter 18 1

2. Why Classify? To study the diversity of life, biologists use a
classification system to name organisms &
group them in a logical manner. 2

3. In other words, naming things.
Taxonomy
Defined:
Discipline of classifying organisms and assigning each organism a universally accepted name.
In other words, naming things. 3

4. Why common names don’t work
Common names vary among languages.
Example:
United Kingdom – Buzzard refers to a hawk
United States – Buzzard refers to a vulture
Red-tailed Hawk
Honey Buzzard
Turkey Vulture 4

5. Early Taxonomists
2000 years ago, Aristotle (384 BC-322 BC) was the first taxonomist
Aristotle divided organisms into plants & animals
He subdivided them by their habitat ---land, sea, or air dwellers

6. Carolus Linnaeus (1707 – 1778) Classified organisms by their structure
Created the system of naming we use today.
His classification system includes 7 levels.
In taxonomy, a group or level of organization is called a taxonomic category or taxon. 6

7. Binomial Nomenclature
“Bi” means 2
“nomial” means naming
Nomenclature means “the system of naming”
Defined:
In binomial nomenclature, each species is assigned a two-part scientific name. 7

8. Example of Binomial Nomenclature
Polar Bear is Ursus maritimus
Ursus: genus
Ursus contains 5 other kinds of bears
maritimus: species
The Latin word, maritimus, refers to the sea.
Polar bears often live on pack ice that floats in the sea. 8

9. Definitions to know Genus: is a group of closely related species
Species: Group of similar organisms that can breed and produce fertile offspring 9

10. Kingdom: Largest taxonomic group, consisting of closely related phyla.
Phylum: Group of closely related classes
Class: Group of similar orders
Order: Group of similar families
Family: Group of genera (genus) that share many characteristics 10

11. What do these mean?...lets see
Here We Go… Polar Bear
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Ursidae
Genus: Ursus
Species: maritimus
What do these mean?...lets see 11

12. What they mean Species: maritimus (lives in marine environment)
Genus: Ursus (kind of bear)
Family: Ursidae (larger category of bears)
Order: Carnivora (meat-eating animals)
Class: Mammalia (warm-blooded, hair, & milk)
Phylum: Chordata (vertebrates)
Kingdom: Animalia (there are 6 kingdoms) 12

13. How to remember: King Phillip Came Over For Green Salad
Kingdom Phylum Class Order Family Genus Species 13

14. Rules of the Game
Uniqueness: Every name has to be unique.
Universality: Zoologists have adopted, by international agreement, a single language to be used on a worldwide basis. All animals are given a generic (common name) and specific name in Latin (scientific name).
These names are in italics or are underlined
(i.e. Homo sapiens or Homo sapiens). 14

15. Phylum
Chordata
Class
Mammalia
Order
Carnivora
Family
Ursidae
Genus Ursus
Species
maritimus

16. Felis Genus species domestica leo margarita
If these three species belong to the same genus, they are descended from a common ancestor.
Felis domestica
domestica
Domestic Cat
Felis
Felis leo
leo
Lion
Felis margarita
margarita
Sand cat`

17. Which TWO are more closely related?

18. A Problem with Traditional Classification
Traditional classification systems relied on
body structure comparisons only
Due to convergent evolution, organisms that
are quite different from each other evolve
similar body structures.
Convergent Evolution: Process by which unrelated organisms independently evolve similarities when adapting to similar environments. 18

19. A Problem with Traditional Classification
Example: The Crab, The barnacle, & The limpet
The barnacle and the limpet have similarly shaped shells & look alike
The crab has a very different body form
Based on anatomy, the barnacle & limpet could be classified together and the crab in a different group. 19

20. This is incorrect because crabs and barnacles are actually related

21. Segmentation Free swimming Larva
Crustaceans
Gastropods
Molted Exoskeleton
Even though they do not look a like, crabs & barnacles are actually related
Segmentation
Free swimming Larva 21

22. Evolutionary Classification
Biologists now group organisms into categories that represent lines of evolutionary descent, not just physical similarities
Evolutionary Classification: Is the strategy of grouping organisms together based on their evolutionary history.

23. Classification Using Cladograms
Cladogram: A diagram that shows the evolutionary relationships among a group of organisms. 23

24. Segmentation Free swimming Larva Molted Exoskeleton
Crustaceans
Gastropods
Molted Exoskeleton
Using Cladograms, you can see that crabs and barnacles share similar characteristics because they both molt & are segmented
Segmentation
Free swimming Larva 24

25. You can also see that ALL have a free swimming larva stage
Crustaceans
Gastropods
Molted Exoskeleton
You can also see that ALL have a free swimming larva stage
Segmentation
Free swimming Larva 25

26. Classification Using Cladograms
Cladogram: A diagram that shows the evolutionary relationships among a group of organisms. 26

27. Draw Your Own Cladogram
Complete Quick lab on p. 453 in text.
Answer the questions in your notes!

29. Classification History
1700s Plantae Animalia
1800s Protista Plantae Animalia
1950s Monera Protista Fungi Plantae Animalia
1990s Eubacteria Archaebacteria Protista Fungi Plantae Animalia 29

30. The Three-Domain System
Recently, as evidence about microorganisms continue to accumulate, biologists came to realize that the Kingdom Monera were composed of 2 distinct groups.
The 6-Kingdom system of classification includes kingdoms:
1. Eubacteria Archaebacteria Protista
4. Fungi Plantae Animalia 30

31. 6 Kingdoms Eubacteria Archaebacteria Protista Fungi Plantae Animalia
Prokaryote
Prokaryote
Eukaryote
Eukaryote
Eukaryote
Eukaryote
Autotroph or
heterotroph
Autotroph or
heterotroph
Autotroph/
heterotroph
Heterotroph
Autotroph
Heterotroph
Includes Algae
Don’t belong in other euk
No cell wall
No chloroplasts
Multicellular
“Ancient Bacteria”
Release enzymes to digest food
Most common bacteria
Cell walls
& Chloroplasts
Live in very hot places
E. ecoli
Pyrococcus furiosus
Paramecium
H. coccinea
Fern frod
Homo sapiens 31

32. These are T4 Bacteriophage
Where do viruses go?
Viruses: Are particles of nucleic acid, protein, and in some cases lipids that can reproduce ONLY by infecting living cells.
Viruses are made of a core of either DNA or RNA surrounded by a protein coat.
These are T4 Bacteriophage
A bacteriophage is a virus which infects bacteria 32

33. Where do viruses go? (continued)
Viruses are not considered alive because they don’t have ALL the characteristics of life.
Example: They can’t reproduce independently
These are the Influenza Viruses
Influenza or "flu" is an infection of the respiratory tract that can affect millions of people every year. 33

34. The End.

35. Honors Biology EOC Review
Complete the following pages in your Bio EOC Booklet:
pages 10, 11, 28, 29

36. Visuals 36

37. Taxonomy Video 37