1. Day 4 – Classification Notes

2. Classifying Organisms Notes
Learning Targets:
Why do we classify organisms?
What language is the classification system written in and why?

3. Why classify organism?
Biologists want to better understand organisms so they organize them.
One tool that they use to do this is classification—the grouping of objects or information based on similarities.
Taxonomy is the branch of biology that groups and names organisms based on studies of their different characteristics.
Biologists who study taxonomy are called taxonomists.

4. Aristotle’s system
The Greek philosopher Aristotle developed the first biological classification system.
Two groups: plants and animals.
He grouped based on their physical structures.

5. Linnaeus’s system of binomial nomenclature
Carolus Linnaeus developed a method of grouping organisms that is the basis of modern classification systems.
Based on physical and structural similarities of organisms.
Modern classification systems use a two-word naming system called binomial nomenclature
Genus and species = the scientific name
The first letter of the Genes is capitalized
The species name is all lower case
The scientific name is written in Latin

6. Latin is the universal langauage

7. Linnaeus’s System of Classification
A group or level of organization is called a or taxon (plural: taxa).  
Linnaeus’s system of classification uses seven taxa.
Modern System
Mnemonic
Kingdom
Phylum
Class
Order
Family
Genus
Species
King
Phillip
Came
Over
For
Grape
Soda

8. Classification of the Grizzly Bear
Linnaeus’s system of classification uses seven taxonomic categories.
This illustration shows how a grizzly bear, Ursus arctos, is grouped within each taxonomic category.
Only some representative species are illustrated for each category above the species level.

9. rufus canadensis Domain Kingdom Phylum Class Order Family Genus
Species
Eukarya
Animalia
Chordata
Mammalia
Carnivora
Felidae
Lynx
Bobcat
rufus
canadensis

10. Problems with Classifying
Classifying species based on their anatomy sometimes posed problems for taxonomists.
Scientists debated which of these three organisms were more closely related—crabs (top left), barnacles (bottom left), and limpets (right).

11. Lets Practice Below are scientific names, correct them! homo sapien
ursus Arctos

12. Lets Practice Below are scientific names, correct them! Homo sapien
ursus Arctos

13. Lets Practice Below are scientific names, correct them! Homo sapien
Ursus arctos

14. Lets Practice Below are scientific names, correct them!
LACTRODECTUS MACTANS
What is this organism’s common name?

15. Which two organisms are most closely related?
Canis lupus
Ursus arctus
Ursus nigres
Homo sapien

16. Red Panda

17. Why is it so hard to classify?

18. Classify the following organisms
Common Name:
Humans
Poison Ivy
E. coli
Euglena
Shelf Fungus
Thermoacidophiles
For Each Common Name: Kingdom: Phylum/Division: Class: Order: Family: Genus: Species: Scientific Name: