Classification of Organisms Classification of Organisms The study

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Classification of Organisms

Classification of Organisms

Classification of Organisms • The study of the kinds and diversity of organisms and

Classification of Organisms • The study of the kinds and diversity of organisms and their evolutionary relationships is called systematics or taxonomy ▫ Taxonomy is the work involved in the original description of a species. ▫ Systematics is the assigning of species into evolutionary groups.

Father of Modern Classification • The modern classification system originated with the work of

Father of Modern Classification • The modern classification system originated with the work of Carolus Linnaeus ▫ he recognized the different species could be grouped into broader categories based on shared characteristics ▫ any grouping of animals that shares a particular set of characteristics forms an assemblage called a taxon

4 Classification. ppt CLASSIFICATION • OBSERVATION: • Many kinds of organisms: • Some similar

4 Classification. ppt CLASSIFICATION • OBSERVATION: • Many kinds of organisms: • Some similar to each other. ▫ wood frog, ▫ leopard frog, ▫ bull frog 08 June 2009

5 Classification. ppt CLASSIFICATION • Others less similar ▫ fish, ▫ frogs, ▫ snakes

5 Classification. ppt CLASSIFICATION • Others less similar ▫ fish, ▫ frogs, ▫ snakes 08 June 2009

6 Classification. ppt CLASSIFICATION • Others very dissimilar ▫ people, ▫ pine trees, ▫

6 Classification. ppt CLASSIFICATION • Others very dissimilar ▫ people, ▫ pine trees, ▫ protozoans 08 June 2009

7 Classification. ppt 08 June 2009 CLASSIFICATION • Why are some kinds similar and

7 Classification. ppt 08 June 2009 CLASSIFICATION • Why are some kinds similar and others NOT similar? Question to be answered later? • How can we make sense of (explain) this diversity? • How can we organize what we know about these organisms?

8 Classification. ppt 08 June 2009 Answer: CLASSIFY • Similar “types” (species) grouped together,

8 Classification. ppt 08 June 2009 Answer: CLASSIFY • Similar “types” (species) grouped together, separated from other species. • Then, group similar groups together, • etc.

9 Classification. ppt 08 June 2009 CLASSIFICATION • Species = kind of organism ▫

9 Classification. ppt 08 June 2009 CLASSIFICATION • Species = kind of organism ▫ fundamental unit in evolution and ecology ▫ more precise definition soon

10 Classification. ppt 08 June 2009 CLASSIFICATION • Necessary? YES !! ~ 1 million

10 Classification. ppt 08 June 2009 CLASSIFICATION • Necessary? YES !! ~ 1 million species of plants, 5 -10 million species of animals + fungi, protists, bacteria no good estimates of numbers of species • Human mind needs to organize information.

11 Classification. ppt 08 June 2009 CLASSIFICATION • Classification system organizes biological knowledge. •

11 Classification. ppt 08 June 2009 CLASSIFICATION • Classification system organizes biological knowledge. • Classification itself is HYPOTHESIS about relationships, similarity because of common ancestry.

12 Classification. ppt 08 June 2009 HYPOTHESIS of relationship

12 Classification. ppt 08 June 2009 HYPOTHESIS of relationship

Modern taxonomists use 7 taxa: • kingdom, phylum, class, order, family, genus and species

Modern taxonomists use 7 taxa: • kingdom, phylum, class, order, family, genus and species ▫ as taxa increase organisms get more specific

14 CLASSIFICATION = Sequence of levels. Classification. ppt 08 June 2009 Linnaean system, from

14 CLASSIFICATION = Sequence of levels. Classification. ppt 08 June 2009 Linnaean system, from Carolus Linnaeus, 1740's Kingdom Phylum Class Order Family Genus Species King Phil called old fat George stupid.

Kingdoms and Domains The three-domain system Bacteria Archaea Eukarya The six-kingdom system Bacteria Archaea

Kingdoms and Domains The three-domain system Bacteria Archaea Eukarya The six-kingdom system Bacteria Archaea Protista Plantae Fungi Animalia The traditional five-kingdom system Monera Protista

16 CLASSIFICATION Classification. ppt 08 June 2009 Woese, 1985 Domain Kingdom Phylum Class Order

16 CLASSIFICATION Classification. ppt 08 June 2009 Woese, 1985 Domain Kingdom Phylum Class Order Family Genus Species Did King Phil call old fat George stupid ?

Kingdoms of Life • In 1969, Robert H. Whitaker classified kingdoms based on cellular

Kingdoms of Life • In 1969, Robert H. Whitaker classified kingdoms based on cellular organization and mode of nutrition ▫ this lead to the formation of the 5 kingdoms

5 Kingdoms of Classification: Monera: comprised of bacteria and cyanobacteria • distinguished by being

5 Kingdoms of Classification: Monera: comprised of bacteria and cyanobacteria • distinguished by being single cell prokaryotes Protista: comprised of Amoeba, Paramecium etc…. • distinguished by being single celled eukaryotes Plantae: multi-cellular photosynthetic eukaryotes • plants have cell walls and are non-motile

5 Kingdoms of Classification: Fungi: multi-cellular heterotrophic eukaryotes • fungi have cell walls and

5 Kingdoms of Classification: Fungi: multi-cellular heterotrophic eukaryotes • fungi have cell walls and usually non-motile • digest organic matter extra-cellularly (outside of cell) and absorb the breakdown products Animalia: multi-cellular heterotrophic eukaryotes • animal cells lack a cell wall and usually motile • feed by ingesting other organisms or parts of other organisms

Monera prokaryote single-cell Protista eukaryote multi-cell Plantae eukaryote multi-cell autotrophic Fungi eukaryote multi-cell heterotrophic,

Monera prokaryote single-cell Protista eukaryote multi-cell Plantae eukaryote multi-cell autotrophic Fungi eukaryote multi-cell heterotrophic, external digestion Animalia eukaryote multi-cell heterotrophic, internal digestion

DOMAINS? ? ? • Many taxonomists have pushed the idea that the five kingdom

DOMAINS? ? ? • Many taxonomists have pushed the idea that the five kingdom system isn’t enough ▫ they feel that organisms share too much similarities and need to be grouped otherwise • the push has led to the addition of 3 domains

3 Domains 1. Archae: bacteria that live in extreme conditions 2. Eubacteria: “true bacteria”

3 Domains 1. Archae: bacteria that live in extreme conditions 2. Eubacteria: “true bacteria” 3. Eukarya: all eukaryotic organisms

Taxonomic Diagrams Mammals Turtles Phylogenetic Tree Lizards and Snakes Crocodiles Birds Mammals Turtles Lizards

Taxonomic Diagrams Mammals Turtles Phylogenetic Tree Lizards and Snakes Crocodiles Birds Mammals Turtles Lizards and Snakes Crocodiles Cladogram Birds

Binomial Nomenclature: • when a species is talked about only the genus and species

Binomial Nomenclature: • when a species is talked about only the genus and species names are used ▫ this is called the scientific name ▫ unique to each type of organism • Required by the International Code of Zoological Nomenclature

Writing Scientific Names • the genus names is always capitalized • both names are

Writing Scientific Names • the genus names is always capitalized • both names are either italicized or underlined ▫ leave a space in the underline between names ex. Homo sapien Felis leo Quercus rubra

Ursus americanus American Black Bear

Ursus americanus American Black Bear

Often Latin names contain clues about the type of organism being described. Canis domesticus

Often Latin names contain clues about the type of organism being described. Canis domesticus : And closely related organisms are often in the same genus, also giving clues about their names Canis lupus: Some names are given after the discoverer, or the discovery location, or even a Latinized descriptive term in English

Conclusion The classification system for organisms have been around for a long time. It

Conclusion The classification system for organisms have been around for a long time. It has endured several changes and is quite complex. Without it modern biology could not exist, much in the same way that a grocery store would go out of business if it did not have a classification system.