1. KEY CONCEPT Organisms can be classified based on physical similarities.

2. Linnaeus developed the scientific naming system still used today.
Taxonomy is the science of naming and classifying organisms.
White oak: Quercus alba
We always write names in the Genus and species.

3. Binomial nomenclature is a two-part scientific naming system.
uses Latin words
scientific names always written in italics
two parts are the genus name and species descriptor

4. A genus includes one or more physically similar species.
Species in the same genus are thought to be closely related.
Genus name is always capitalized.
A species descriptor is the second part of a scientific name.
always lowercase
always follows genus name; never written alone
Tyto alba

5. Scientific names help scientists to communicate.
Some species have very similar common names.
Some species have many common names.

6. Linnaeus’ classification system has seven levels.
Each level is included in the level above it.
Levels get increasingly specific from kingdom to species.

7. The Linnaean classification system has limitations.
Linnaeus taxonomy doesn’t account for molecular evidence.
The technology didn’t exist during Linneaus’ time.
Linnaean system based only on physical similarities.

8. Physical similarities are not always the result of close relationships.
Genetic similarities more accurately show evolutionary relationships.

9. Racoon
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Procyonidae
Genus: Procyon
Species: P. lotor
Red Panda
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Ailuridae
Genus: Ailurus
Species: A. fulgens

10. KEY CONCEPT Modern classification is based on evolutionary relationships.
DNA!!!
De-oxy Ribo Nucleic Acid

11. Cladistics is classification based on common ancestry.
Phylogeny is the evolutionary history for a group of species.
evidence from living species, fossil record, and molecular data
shown with branching tree diagrams

12. Evolutionary trees. classification based on common ancestry
species placed in order that they descended from common ancestor

13. Classification is always a work in progress.
The tree of life shows our most current understanding.
New discoveries can lead to changes in classification.
Until 1866: only two kingdoms, Animalia and Plantae
Animalia
Plantae

14. Classification is always a work in progress.
The tree of life shows our most current understanding.
New discoveries can lead to changes in classification.
Until 1866: only two kingdoms, Animalia and Plantae
Plantae
Animalia
1866: all single-celled organisms moved to kingdom Protista
Protista

15. Classification is always a work in progress.
The tree of life shows our most current understanding.
New discoveries can lead to changes in classification.
Until 1866: only two kingdoms, Animalia and Plantae
Animalia
Protista
Plantae
1866: all single-celled organisms moved to kingdom Protista
1938: prokaryotes moved to kingdom Monera
Monera

16. Classification is always a work in progress.
The tree of life shows our most current understanding.
New discoveries can lead to changes in classification.
Until 1866: only two kingdoms, Animalia and Plantae
Protista
Plantae
Animalia
1866: all single-celled organisms moved to kingdom Protista
1938: prokaryotes moved to kingdom Monera
Fungi
1959: fungi moved to own kingdom
Monera

17. Classification is always a work in progress.
The tree of life shows our most current understanding.
New discoveries can lead to changes in classification.
Until 1866: only two kingdoms, Animalia and Plantae
Animalia
Protista
Fungi
Plantae
1866: all single-celled organisms moved to kingdom Protista
1938: prokaryotes moved to kingdom Monera
Archea
Bacteria
1959: fungi moved to own kingdom
1977: kingdom Monera split into kingdoms Bacteria and Archaea

18. Kingdom eubacteria.
one of largest groups on Earth
classified by shape, need for oxygen, and diseases caused

19. Kingdom Archaebacteria .
cell walls chemically different from bacteria
differences discovered by studying RNA
known for living in extreme environments

20. Kingdom Protista

21. Kingdom Plantae

22. Kingdom Fungi

23. Kingdom Animalia

24. Bacteria and archaea can be difficult to classify.
transfer genes among themselves outside of reproduction
blurs the line between “species”
more research needed to understand prokaryotes
bridge to transfer DNA