1. Unit 11: Classification
Ch. 14 Classification
Taxonomy = branch of biology that deals w/ naming & classifying organisms.
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2. Why Things Are Classified?
What does it mean to classify?
to group based on similarities
Examples of classifying in everyday life…?
Why are organisms/objects classified?
easier to “find”
show shared traits
show relationships among living & extinct species
What does it mean to classify? to group things together based on similarities Why do we have 2 names?
Examples of classifying in everyday life… food in supermarket, books in library, subjects in school….
Why are organisms classified? make things easier to find show that things share certain traits Provides a framework in which to study the relationships among living and extinct species

3. Why Things Are Classified?
What is a dichotomous key?
a tool used for classification
At each step, the user is given two choices.
Each alternative leads to another question…
until the item is identified.
What are two ways to make a dichotomous key?
branching “tree” diagram
list format
How are organisms classified? Taxonomists group organisms, from very broad characteristics to very specific ones based on evolutionary relationships. A group of organisms is called a taxon. There are 8 taxons
Characteristics include: Structural similarities, Breeding behaviors, Geographical distribution, Chromosome Comparison, Biochemistry
What tools do we use to classify organisms? dichotomous keys….method for determining the identity of something (like the name of a butterfly, a plant, a lichen, or a rock) by going through a series of choices that leads the user to the correct name of the item. Dichotomous means "divided in two parts". At each step of the process of using the key, the user is given two choices; each alternative leads to another question until the item is identified. (It's like playing 20 questions.) For example, a question in a dichotomous key for trees might be something like, "Are the leaves flat or needle-like?" If the answer was "needle-like," then the next question might be something like, "Are the needles in a bunch or are they spread along the branch?" Eventually, when enough questions have been answered, the identity of the tree is revealed.

4. Why Things Are Classified?
How are organisms classified?
very broad characteristics  very specific
Based on…?
evolutionary relationships
What is a group of organisms called?
taxon (plural = taxa)
How many taxa are there?
8 (Domain  species)
How are organisms classified? Taxonomists group organisms, from very broad characteristics to very specific ones based on evolutionary relationships. A group of organisms is called a taxon. There are 8 taxons
Characteristics include: Structural similarities, Breeding behaviors, Geographical distribution, Chromosome Comparison, Biochemistry
Domain
Characteristics used include:
structural similarities, breeding behaviors, geographical distribution, DNA, biochemistry

5. Early Classification Who devised the 1st classification system?
Aristotle
How did he classify organisms?
1. plants
by type of stem
2. animals
by environment in which they live
According to Aristotle, which of these 3 animals would be classified more closely?
Aristotle (Greek philosopher) >2000 years ago divided organisms into 2 groups
Early classification did not classify organisms by ancestry b/c it was not believed organisms evolved

6. Beginning of Modern Classification
Who was the “Father of Modern Taxonomy”?
Carolus Linnaeus
How did he classify organisms?
2 main groups = kingdoms
plants
animals
Also used:
genus
~similar species
species
~organisms w/ similar traits
1735
In Linnaeus’ system… kingdom largest group of living things (think of it as a set & smaller categories like genus & species as subsets)
Made a # of changes to Aristotle’s system…
1. classified plants & animals into more groups
2. based his system on specific traits
3. gave organisms names that described their traits (2 parts… genus & species)

7. Beginning of Modern Classification
How did Linnaeus name organisms?
used binomial nomenclature
2 name system (unique to every species)
written: Genus species or Genus species
Genus = 1st name, capitalized
species = 2nd name, lower case & descriptive
Ex. Common name Genus & species
Humans Homo sapiens
White Oak tree Quercus alba
Red Oak tree Quercus rubra
Bottlenose dolphin Tursiops truncatus
2 name system similar to a person’s name
written as Genus species or Genus species Genus = 1st name, capitalized species = 2nd name, lower case & descriptive names are Italicized or underlined, underline when writing by hand

8. Beginning of Modern Classification
Why don’t we use common names?
two organisms can have same common name, but not sci. name
scientific names rarely change
scientific names are written in same language around the world
scientific names rarely change b/c Latin is a “dead” language that does not change
scientific names are written in same language around the world… Latin b/c a “dead” language that does not change
Many different types of shrimp… we usually just call the “shrimp” not even white, brown, pink, etc… (their full common names…) scientific names help reduce confusion amongst scientists & scholars

9. How Scientists Classify Today
Our current classification system reflects…?
relationships
based on phylogeny (evolutionary ancestry)
According to the phylogenetic tree on the right, who are humans most closely related to?
based on phylogeny (evolutionary ancestry)
Classification is not fixed Systems of classification are open to change in response to new data
How are evolutionary relationships determined?
structural similarities
breeding behaviors
geographical distribution
chromosome comparison
biochemistry

10. How Scientists Classify Today
Can classification systems change?
Yes.
Why?
With scientific advancements, we gain new data & learn more about organisms…

11. How Scientists Classify Today
Classification systems we’re going to discuss:
5 Kingdom system
Monera, Protista, Fungi, Plantae, Animalia
6 Kingdom system
Monera split into Archaebacteria & Eubacteria… other 4 kingdoms remain same
3 Domain system
Archaea, Bacteria, Eukaryota (Eukarya)
4 kingdoms (Protista, Fungi, Plantae, Animalia) grouped in Eukaryota
6 Kingdom system  Monera split into Archaebacteria & Eubacteria… other 4 kingdoms remain same (Protista, Fungi, Plantae, Animalia)
3 Domain system  Archaea, Bacteria, Eukaryota (which includes 4 kingdoms… Protista, Fungi, Plantae, Animalia)

12. Where would Domain belong in this diagram?
Each successive classification category contains more different types of organisms than the preceding category.

13. How Scientists Classify Today
When using the 5 or 6 Kingdom system…
Which group is largest & most inclusive?
Kingdom
Which is smallest & least inclusive?
species
Kingdom = country USA
Phylum = state CT
Class = county Fairfield
Order = town Darien
Family = neighborhood Noroton Heights???
Genus = street High School Lane
Species = house number 80

14. How Scientists Classify Today
When using the 3 Domain system…
Which group is largest & most inclusive?
domain
Which group is smallest & least inclusive?
species
Domain
Eukaryota
Domain
Each successive classification category contains more different types of organisms than the preceding category.

15. How Scientists Classify Today
What is a species?
group of organisms capable of mating with one another in nature to produce fertile offspring

16. How Scientists Classify Today
A trick to help you remember all the major classification groups…
Did  Domain
Katy  Kingdom
Perry  Phylum
Come  Class
Over  Order
For  Family
Good  Genus
Sushi?  species
Each successive classification category contains more different types of organisms than the preceding category.
Another trick…
Did DOMAIN
King KINGDOM
Phillip PHYLUM
Come CLASS
Over ORDER
From FAMILY
Germany GENUS
Sunday SPECIES

17. How Scientists Classify Today
What is the relationship among the levels?
from Domain down, each level has a new set of criteria that must be shared
Organisms that are more closely related 
share more levels
DOMAIN Eukaryota
As move down, each category below has fewer types of organisms than the one above it…. As move up, each category above contains more different types of organisms than the category below.
from Domain down, each level has a new set of criteria that must be shared… Ex in pic…. Domain  all have nucleus, kingdom  all are animals (have nucleus AND multicellular heterotrophs that do not have cell walls), phylum  all have spines/backbones (and are animals with have nucleus AND multicellular heterotrophs that do not have cell walls), class  all give birth to live young, feed the young milk, are covered w/ fur, have mammary glands (AND have spines/backbones (and are animals with have nucleus AND multicellular heterotrophs that do not have cell walls)…. Order  eat meat…. AND….. Every characteristic from above

18. Once an organism shares a more specific taxon (lower group) it MUST share the more unifying taxa (higher groups)
How many levels of classification do we share with dolphins?
How many levels of classification do we share with dolphins? 4….Domain, Kingdom, Phylum, Class

20. Domain: Archaea 6 Kingdom system: Archaebacteria 5 Kingdom system: Monera
prokaryotic
unicellular
feeding
heterotrophic or autotrophic
other characteristics
older, less complex bacteria
live in extreme environments
examples
bacteria:
in salt lakes
at hydrothermal vents
KINGDOM MONERA (monerans) - *1 cell *no true nucleus - prokaryote (genetic material scattered and not enclosed by a membrane) *some move (flagellum); others don‘t *some make their own food (autotrophic); others can't make their own food (heterotrophic) *examples - bacteria, blue-green bacteria (cyanobacteria)  split into 2 domains Archaea & Eubacteria

21. Domain: Bacteria 6 Kingdom system: Eubacteria 5 Kingdom system: Monera
prokaryotic
unicellular
feeding
heterotrophic or autotrophic
other characteristics
modern, more complex bacteria
evolved from Archaea
most common & very diverse
free-living or pathogenic
examples
Staphylococcus
E. coli
cyanobacteria
Staphylococcus
cyanobacteria
Most common & very diverse, heterotrophic or autotrophic, free-living or pathogenic
KINGDOM MONERA (monerans) - *1 cell *no true nucleus - prokaryote (genetic material scattered and not enclosed by a membrane) *some move (flagellum); others don‘t *some make their own food (autotrophic); others can't make their own food (heterotrophic) *examples - bacteria, blue-green bacteria (cyanobacteria)  split into 2 domains Archaea & Eubacteria

22. Domain: Eukaryota All are eukaryotic 4 of the 5 (or 6) kingdoms
1. Protista
2. Fungi
3. Plantae
4. Animalia
KINGDOM PROTISTA (protists) - *1 cell *have a true nucleus – eukaryote *some move (cilia, flagella, pseudopodia); others don‘t *some are autotrophic; others are heterotrophic *examples - amoeba, diatom, euglena, paramecium, some algae (unicellular), etc
KINGDOM FUNGI - *multicellular *have nuclei *mainly do not move from place to place *heterotrophic (food is digested outside of fungus) *examples - mushroom, mold, puffball, shelf/bracket fungus, yeast, etc.
KINGDOM PLANTAE (plants) - *multicellular *have nuclei *do not move *autotrophic *examples - multicellular algae, mosses, ferns, flowering plants (dandelions, roses, etc.), trees, etc
KINGDOM ANIMALIA (animals) - *multicellular *have nuclei *do move *heterotrophic *examples - sponge, jellyfish, insect, fish, frog, bird, man

23. Domain: Eukaryota 1. Kingdom: Protista
Amoeba
eukaryotic
mostly unicellular
feeding
heterotrophic or autotrophic
other characteristics
can be plant-like, animal-like, or fungus-like
examples
Amoeba
Paramecium
Euglena
algae
Paramecium
Euglena
algae
KINGDOM PROTISTA (protists) - *1 cell *have a true nucleus – eukaryote *some move (cilia, flagella, pseudopodia); others don‘t *some are autotrophic; others are heterotrophic *examples - amoeba, diatom, euglena, paramecium, some algae (unicellular), etc

24. Domain: Eukaryota 2. Kingdom: Fungi
eukaryotic
multicellular***
feeding
heterotrophic
digest food outside & absorb nutrients
other characteristics
cell walls made of chitin
decomposers & parasites
examples
mushrooms
molds
yeast (*** unicellular)
Decomposers & parasites
KINGDOM FUNGI - *multicellular *have nuclei *mainly do not move from place to place *heterotrophic (food is digested outside of fungus) *examples - mushroom, mold, puffball, shelf/bracket fungus, yeast, etc.

25. Domain: Eukaryota 3. Kingdom: Plantae
eukaryotic
multicellular
feeding
autotrophic
photosynthesis
other characteristics
cell walls made of cellulose
produce oxygen
examples
mosses
ferns
grasses
shrubs
trees
KINGDOM PLANTAE (plants) - *multicellular *have nuclei *do not move *autotrophic *examples - multicellular algae, mosses, ferns, flowering plants (dandelions, roses, etc.), trees, etc

26. Domain: Eukaryota 4. Kingdom: Animalia
eukaryotic
multicellular
feeding
heterotrophic
other characteristics
no cell wall
examples
invertebrates
insects
worms
sponges
corals
vertebrates
fish
birds
amphibians
reptiles
mammals
KINGDOM ANIMALIA (animals) - *multicellular *have nuclei *do move *heterotrophic *examples - sponge, jellyfish, insect, fish, frog, bird, man

28. Links