Classification/Taxonomy Chapter 18

Why Classify? Why Classify?

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

Why common names don’t work Common names vary among languages and regions. Example: United Kingdom – Buzzard refers to a hawk United States – Buzzard refers to a vulture Red-tailed HawkHoney BuzzardTurkey Vulture

5 Aristotle 384 BC 1 st scientist to Classify organisms 1 st scientist to Classify organisms either plants or animals either plants or animals

Carolus Linnaeus (1707 – 1778) (1707 – 1778) Created the system of naming we use today. Created the system of naming we use today. In taxonomy, a group or level of organization is called a taxonomic category or taxon. In taxonomy, a group or level of organization is called a taxonomic category or taxon.

Binomial Nomenclature “Bi” means 2 “Bi” means 2 “nomial” means number “nomial” means number “Nomen” means name “Nomen” means name “Clature” means the system of “Clature” means the system of Defined: In binomial nomenclature, each species is assigned a two-part scientific name.

8 Binomial Nomenclature Carolus Linnaeus Carolus Linnaeus In binomial nomenclature, each species is assigned a two-part scientific name. In binomial nomenclature, each species is assigned a two-part scientific name. The scientific name is always written in italics or underlined. The scientific name is always written in italics or underlined. The first word (the genus) is capitalized The first word (the genus) is capitalized The second word (the species) is lowercased. The second word (the species) is lowercased. EX- Genus species or Genus species Humans- Homo sapien

Example of Binomial Nomenclature Polar Bear is Ursus maritimus Polar Bear is Ursus maritimus Ursus: genus Ursus: genus Ursus contains 5 other kinds of bears Ursus contains 5 other kinds of bears maritimus: species maritimus: species The Latin word, maritimus, refers to the sea. The Latin word, maritimus, refers to the sea. Polar bears often live on pack ice that floats in the sea. Polar bears often live on pack ice that floats in the sea.

10 Linnaeus's System of Classification A group or level of organization is called a taxonomic category, or taxon A group or level of organization is called a taxonomic category, or taxon Linnaeus had 7- Linnaeus had 7- Kingdom “King Phylum Phillip Class Came Order Over Family For Genus Great Species Spaghetti”

Definitions to know Genus : is a group of closely related species Genus : is a group of closely related species Species : Group of similar organisms that can breed and produce fertile offspring Species : Group of similar organisms that can breed and produce fertile offspring

Family: Group of genera that share many Family: Group of genera that share many characteristics characteristics Order: Group of similar families Order: Group of similar families Class: Group of similar orders Class: Group of similar orders Phylum: Group of closely related classes Phylum: Group of closely related classes Kingdom: Largest taxonomic group, Kingdom: Largest taxonomic group, consisting of closely related consisting of closely related phyla. phyla.

Here We Go… Polar Bear Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Carnivora Family: Ursidae Genus: Ursus Species: maritimus What do these mean?...lets see

What they mean Kingdom: Animalia (there are 6 kingdoms) Phylum: Chordata (vertebrates) Class: Mammalia (warm-blooded, hair, & milk) Order: Carnivora (meat-eating animals) Family: Ursidae (larger category of bears) Genus: Ursus (kind of bear) Species: maritimus (lives in marine environment) *Do NOT have to write*

How to remember: King Phillip Came Over For Green Salad Kingdom Phylum Class Order Family Genus Species

Rules of the Game Uniqueness: Every name has to be unique. Universality: Zoologists have adopted, by international agreement, a single language to be used on a worldwide basis. All animals are given a generic (common name) and specific name in Latin (scientific name). These names are in italics or are underlined (i.e. Homo sapiens).

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Modern Three-Domain System As scientists further analyzed cell structure and DNA, a broader category was added- As scientists further analyzed cell structure and DNA, a broader category was added- The domain is the most inclusive taxonomic category; larger than a kingdom The domain is the most inclusive taxonomic category; larger than a kingdom The three domains are: The three domains are: Bacteria : kingdom Eubacteria Bacteria : kingdom Eubacteria Archaea,: kingdom Archaebacteria; Archaea,: kingdom Archaebacteria; Eukarya :Kingdom ANIMALIA, protista, fungi, plantae (all have eukaryotic cells) Eukarya :Kingdom ANIMALIA, protista, fungi, plantae (all have eukaryotic cells)

Kingdoms Eubacteria Archaebacteria Protista Plantae Fungi Animalia DOMAIN EUKARYA DOMAIN ARCHAEA DOMAIN BACTERIA Section 18-3 Cladogram of Six Kingdoms and Three Domains Go to Section:

Modern 6 Kingdom System Recently, as evidence about microorganisms continue to accumulate, biologists came to realize that the Kingdom Monera were composed of 2 distinct groups. Recently, as evidence about microorganisms continue to accumulate, biologists came to realize that the Kingdom Monera were composed of 2 distinct groups. The 6-Kingdom system of classification includes kingdoms: The 6-Kingdom system of classification includes kingdoms: 1. Eubacteria 2. Archaebacteria 3. Protista 4. Fungi 5. Plantae 6. Animalia

6 Kingdoms Eubacteria Archaebacteria Protista Fungi Plantae Animalia E. ecoliParamecium Fern frod H. coccineaHomo sapiensPyrococcus furiosus Prokaryote Eukaryote Autotroph or heterotroph Autotroph or heterotroph Autotroph/ heterotroph Heterotroph Autotroph Most common bacteria Live in very hot places Includes Algae Don’t belong in other euk Cell walls & Chloroplasts Release enzymes to digest food No cell wall No chloroplasts Multicellular “Ancient Bacteria”

22 Checkpoint Questions: 1. How are living things organized for study? 2. Describe the system for naming species that Linnaeus developed. 3. What are the seven taxonomic categories of Linnaeus’s classification system? 4. Why do scientists avoid using common names when discussing organisms? 5. What is significant about members of the same species?