1. Chapter 17: Organizing Life’s Diversity
Taxonomy
Chapter 17: Organizing Life’s Diversity

2. What is Taxonomy?
Discipline of classifying organisms and assigning each organism a universally accepted name.

3. Why Classify?
To study the diversity of life, biologists use a classification system to name organisms and group them in a logical manner.
When taxonomists classify organisms, they organize them into groups that have biological significance.

4. Common Names vs. Scientific Names
Common Names can be confusing one organism can have many different names
The Cougar is also known as a: Puma, Mountain Lion or Catamount
Each organism only has ONE scientific name (species name)
No matter where you are in the world the Cougar is Felis concolor

5. Assigning Scientific Names
Aristotle was a Greek philosopher who was the first to classify or group living things.
He classified organisms into two groups:
Plants and Animals
He subdivided those groups as well.
Plants were subdivided into: Herbs, Shrubs and Trees
Animals were subdivided based on their habitat and physical characteristics

6. Assigning Scientific Names
A Swedish botanist named Carolus Linnaeus developed Binomial Nomenclature, a two-word naming system for naming all species on earth.
It is based on physical and structural similarities
Still used today

7. Why does everything have a weird name in Biology?
Everything in science is named using Latin.
Why?
Latin is a dead language and won’t change meanings with slang or invention.
“That is SO gay!!!”
Example:
Merriam Webster Dictionary definition:
Gay – (gA) adjective; 1 a : happily excited : MERRY <in a gay mood> b : keenly alive and exuberant : having or inducing high spirits <a bird's gay spring song>2 a : BRIGHT, LIVELY <gay sunny meadows> b : brilliant in color

8. 4 Reasons for using Latin
dead language and will not change
not misleading like a common name
more descriptive
basis for many other languages; English, French, Spanish, Italian and Portuguese

9. Binomial Nomenclature
Each organism has a name consisting of two words
Examples:
Homo sapiens Tyto alba
Common Name: Human Common Name: Barn Owl

10. Binomial Nomenclature
Homo sapiens Tyto alba
The first part of the scientific name is the genus. This word is always written first and the first letter is capitalized. It appears in italics or is underlined.

11. Binomial Nomenclature
Homo sapiens Tyto alba
The second part of the scientific name is the specific epithet or species name. This word is always written second and the first letter is lower-case.
It appears in italics or is underlined.

12. The 8 Levels of Classification
They are, from largest to smallest
Domain (this is a relatively new level separates Archaea, Bacteria and Eukaryota)
Kingdom (separates plants from animals)
Phylum (separates into major groups within the Kingdom; plural: phyla)
Class (breaks Phyla down into smaller groups)
Order (even more specific)
Family (very similar characteristics)
Genus (reproductive grouping)
Species (most specific)

13. Come Did King Phillip Over For Good Soup Species Genus Family Order
Class
For
Phylum
Good
Kingdom
Soup
Domain

14. 8 levels of Classification
You vs. Barn Owl
Kingdom:
Animalia
Phylum:
Chordata
Class:
Mammalia
Order:
Primates
Family:
Hominidae
Genus:
Homo
Species:
H. sapiens
Kingdom:
Animalia
Phylum:
Chordata
Class:
Aves
Order:
Strigiformes
Family:
Tytonidae
Genus:
Tyto
Species:
T. alba

15. THINKING CRITICALLY Organism Kingdom Phylum Class Order Family Genus
Cat
Wolf
Fly
Kingdom
Animalia
Phylum
Chordata
Arthropoda
Class
Mammalia
Insecta
Order
Carnivora
Diptera
Family
Felidae
Canidae
Muscidae
Genus
Felis
Canis
Musca
Species
F. domesticus
C. lupus
M. domestica
Have students study this chart. The next slide lists three questions to answer using this chart. You may have to advance to the next slide, let students read the question and then come back to the chart so they can find the answer.

16. THINKING CRITICALLY What are the kingdom and class of Musca domestica?
From the table, which 2 animals are most closely related?
3. At what classification level does the evolutionary relationship between cats and wolves diverge (become different)?
Animal; insect
Cat and Wolf
Family Level

17. EVOLUTIONARY CLASSIFICATION
Biologists group organisms into categories that represent lines of evolutionary descent, or phylogeny, not just physical similarities.
Define Phylogeny: The study of evolutionary relationships among organisms.

18. Classification using Cladograms
Cladograms are diagrams that use derived characteristics to illustrate evolutionary relationships.
Definition of Clade: A group of organisms, such as a species, whose members share homologous features derived from a common ancestor.

19. EVOLUTIONARY CLASSIFICATIONB C D E F
Clade or
lineage
TIME
The American Heritage® Dictionary of the English Language, Third Edition copyright © 1992 by Houghton Mifflin Company. Electronic version licensed from INSO Corporation; further reproduction and distribution restricted in accordance with the Copyright Law of the United States. All rights reserved.
Speciation: formation of two
new species from one

20. Classification using Cladograms
The cladogram on the next slide shows the evolutionary
relationship among several vertebrates.

21. CLADOGRAM Jaws Lungs Claws or Nails Feathers Hagfish Fish Frog Lizard
Pigeon
Mouse
Chimp
Fur &
Mammary
Glands

23. Cladogram
“Mini-Lab”

24. Using a Cladogram to Show Relationships
Procedure
The following table shows the presence or absence of six derived traits in the seven dinosaurs that are labeled A - G.
Use the information listed in the table below to answer the following questions.

25. Using a Cladogram to Show Relationships
Derived Traits of Dinosaurs
Dinosaur Trait
Dino A
Dino B C D
Dino E F
Dino G
Hole in hip socket
Yes
Extension of pubis bone No
Unequal enamel on teeth
Skull has “shelf” in back
Grasping hand
Three-toed hind foot

26. ANALYSIS 1. Classify Complete the missing information on the right side of the partially completed cladogram. A B C D E F G
Three-Toed Hind Foot 6 2 5
Grasping Hand 2 4 1