Classification

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Why do we need to classify things?

1)To study how diverse life is

2)To organize everything that we see in the world.

WHAT CLASSIFICATION USED TO LOOK LIKE…

1)It’s estimated that the earth formed around 4.6 billion years ago

- Was not possible for life to exist- Temp was too hot for water to exist in a liquid form

- Constant volcanic activity

- Atmosphere probably consisted of helium and hydrogen

3.8 BILLION YEARS AGO…

-Evidence suggests that life came to be around this time.-What type of life?

- Single celled bacteria- Possibly cyanobacteria (blue-green algae)

- It would have been fairly easy to classify organisms at this time, because there weren’t very many life forms that existed.

SO THEN WHAT?...-For around 3 billions years, life stayed very simple

- mostly single-celled organisms

-Life did not evolve much

-New life forms were not really developing

-Classification would have been very simple

550 MILLION YEARS AGO…

Cambrian Explosion-Why call it the “explosion?”

-Several new types of life begin to form

- sea plants, land plants, sea animals, land animals.

-As life continues to become more complex there is a greater need to figure out what makes things different from each other.

400-430 MILLION YEARS AGO…-Insects begin to appear…

- Scorpions, spiders, centipedes, etc…

-Plants become more complex- Forests begin to appear

-Now there is a need to distinguish how plants are different from each other

245 MILLION YEARS AGO…

-Dinosaurs-Reptiles-Small mammals-Birds

65 MILLION YEARS AGO…

Mammals begin to dominate life on earth

How does classification fit into all of this?

-As time went on, life became much more complex and diverse-Because of that, it’s necessary to distinguish one life form from another

Example:- We can’t just call a dog a mammal and be done with it.

-An elephant is a mammal too.

- You have to keep getting more specific

- Like almost everything in science, there is a specific process used to do classify

1. Why Classify?a. To study the diversity of lifeb. To organize and name organisms

2. Why give scientific names?a. Common names are misleading

Finding Order in Diversity

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jellyfish silverfish star fish

None of these animals are fish!

Some organisms have several common names

This cat is commonly known as:

•Florida panther

•Mountain lion

•Puma

•CougarScientific name: Felis concolor

Scientific name means “coat of one color”

Why Scientists Assign Scientific Names to Organisms

Grizzly bear Black bear Giant panda

Red fox Abert squirrel

Coral snake

Sea star

KINGDOM Animalia

PHYLUM Chordata

CLASS Mammalia

ORDER Carnivora

FAMILY Ursidae

GENUS Ursus

SPECIES Ursus arctos

Hierarchical Ordering of Classification

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As we move from the kingdom level

to the species level, more and more members are

removed.

Each level is more specific.

Kingdom

Phylum

Class

Order

Family

Genus

SpeciesGo to Section:

Linnaeus’s System of HierarchyLeast

specific

Most specific

1. Which of the following contains all of the others?

a. Family c. Class

b. Species d. Order

2. Based on their names, you know that the baboons Papio annubis and Papio cynocephalus do not belong to the same:

a. Family c. Order

b. Genus d. Species

Linnaeus: The Father of Modern Taxonomy

Carolus Linnaeus

1. 1732: Carolus Linnaeus developed system of classification – binomial nomenclature

a. Two name naming system

b. Gave organisms 2 names

Genus (noun) and species (adjective)

Rules for naming organisms

1. Written is Latin (unchanging)

2. Genus capitalized, species lowercase

3. Both names are italicized or underlined

EX: Homo sapiens: wise / thinking man

2. Each organism is given a scientific name – even newly discovered species

Kingdom Archaebacteria

Cell Type Prokaryote

Number of Cells Unicellular

Nutrition Autotroph or Heterotroph

Location Extreme Environments Volcanoes, Deep Sea Vents, Yellowstone Hot Springs

Examples Methanogens Thermophiles

Kingdom Eubacteria

E. coli

Streptococcus

Cell Type ProkaryoteNumber of Cells UnicellularNutrition Autotroph or

HeterotrophExamples Streptococcus,

Escherichia coli (E. coli)

Kingdom Protista

Paramecium

Green algae

Amoeba

Cell Type Eukaryote

Number of Cells Most Unicellular, some multicellular

Nutrition Autotroph or Heterotroph

Examples Amoeba, Paramecium, Euglena,

The “Junk-Drawer” Kingdom

Kingdom Plantae

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Ferns : seedless vascular

Sunflowers: seeds in flowers

Douglas fir: seeds in cones

Mosses growing on trees

Cell Type EukaryoteNumber of Cells MulitcellularNutrition AutotrophExamples Mosses, ferns,

conifers, flowering plants

Kingdom Fungi

Mildew on Leaf

Mushroom

Cell Type Eukaryote

Number of Cells Most multicelluar, some unicelluar

Nutrition Heterotroph

Example Mushroom, yeast, mildew, mold

Most Fungi are DECOMPOSERS

Kingdom Animalia

Sage grouse

Poison dart frog

Bumble bee

sponge

jellyfish

hydra

Cell Type EukaryoteNumber of Cells MulticellularNutrition HeterotrophExamples Sponges,

worms, insects, fish, mammals

LIFE’S ADAPTATIONS:

Symbiosis – an ongoing relationship in which two species live closely together.1. Mutualism – both benefit

2. Commensalism – one benefits and the other is neither helped or harmed.

3. Parasitism – one benefits and the other is harmed. Ex: ticks on a dog.

Other interactions Predation-interaction where one

organism captures and feeds on another.

Competition- interaction where one or more organisms vie for the same resource.

Interactions Predation +/- Competition -/- Symbiosis

– Mutualism +/+– Commensalism +/0– Parasitism +/-