Classification and Taxonomy

What is Taxonomy?

Discipline of classifying organisms and assigning each organism a universally accepted name.

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.

Common Names vs.

Scientific NamesCommon Names can be confusing

one organism can have many different namesThe 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

Assigning Scientific NamesAristotle 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

Assigning Scientific Names A Swedish botanist named

Carl 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

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.

Example: “That is SO gay!!!”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

4 Reasons for using Latin

1. dead language and will not change

2. not misleading like a common name

3. more descriptive

4. basis for many other languages; English, French, Spanish, Italian and Portuguese

Binomial Nomenclature Each organism has a name consisting

of two words

Examples:

Homo sapiens Tyto alba

Common Names:

HUMAN

Barn Owl

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.

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.

The 8 Levels of ClassificationThey are, from largest to smallest

1.Domain (this is a relatively new level separates Archaea, Bacteria and Eukaryota)

2.Kingdom (separates plants from animals)

3.Phylum (separates into major groups within the Kingdom; plural: phyla)

4.Class (breaks Phyla down into smaller groups)

5.Order (even more specific)

6.Family (very similar characteristics)

7.Genus (reproductive grouping)

8.Species (most specific)

Domain

Kingdom

Phylum

Class

Order

Family

Genus

Species

DidKingPhillipComeOverForGoodSoup

8 levels of Classification

Kingdom: AnimaliaPhylum: ChordataClass: AvesOrder: StrigiformesFamily: TytonidaeGenus: Tyto

Species: T. alba

Kingdom: Animalia

Phylum: ChordataClass: MammaliaOrder: PrimatesFamily: HominidaeGenus: Homo

Species: H. sapiens

Miss Cook vs. Barn Owl

THINKING CRITICALLYOrganism

Cat Wolf Fly

Kingdom Animalia Animalia Animalia

Phylum Chordata Chordata Arthropoda

Class Mammalia Mammalia

Insecta

Order Carnivora Carnivora Diptera

Family Felidae Canidae Muscidae

Genus Felis Canis Musca

Species F. domesticus C. lupus M. domestica

THINKING CRITICALLY1. What are the kingdom

and class of Musca domestica?

2. 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