1 Classification Chapter 17

2 There are 13 billion known species of organisms There are 13 billion known species of organisms 1.75 million have been named and described by scientists million have been named and described by scientists. This is only 5% of all organisms that ever lived!!!!! This is only 5% of all organisms that ever lived!!!!! New organisms are still being found and identified New organisms are still being found and identified Species of Organisms 17-1

3 What is Classification? Classification is the arrangement of organisms into orderly groups based on their similarities Classification is also known as taxonomy Taxonomists are scientists that identify & name organisms

4 Benefits of Classifying Accurately & uniformly names organisms Accurately & uniformly names organisms Prevents misnomers such as starfish & jellyfish that aren't really fish Prevents misnomers such as starfish & jellyfish that aren't really fish Uses same language (Latin or some Greek) for all names Uses same language (Latin or some Greek) for all names Sea”horse”??

5 Confusion in Using Different Languages for Names

6 Latin Names are Understood by all Taxonomists

7 Early Taxonomists 2000 years ago, Aristotle was the first taxonomist 2000 years ago, Aristotle was the first taxonomist Aristotle divided organisms into plants & animals Aristotle divided organisms into plants & animals He subdivided them by their habitat ---land, sea, or air dwellers He subdivided them by their habitat ---land, sea, or air dwellers

8 Early Taxonomists John Ray, a botanist, was the first to use Latin for naming John Ray, a botanist, was the first to use Latin for naming His names were very long descriptions telling everything about the plant His names were very long descriptions telling everything about the plant

9 Carolus Linnaeus 1707 – th century taxonomist Classified organisms by their structure Developed naming system still used today

10 Carolus Linnaeus Called the “Father of Taxonomy” Called the “Father of Taxonomy” Developed the modern system of naming known as binomial nomenclature Developed the modern system of naming known as binomial nomenclature Two-word name (Genus & species) Two-word name (Genus & species)

11 Standardized Naming Binomial nomenclature used Binomial nomenclature used Genus species Genus species Latin or Greek Latin or Greek Italicized in print Italicized in print Capitalize genus, but NOT species Capitalize genus, but NOT species Underline when writing Underline when writing Turdus migratorius American Robin

12 Binomial Nomenclature Which TWO are more closely related?

13 Classification Groups Taxon ( taxa-plural) is a category into which related organisms are placed Taxon ( taxa-plural) is a category into which related organisms are placed There is a hierarchy of groups (taxa) from broadest to most specific There is a hierarchy of groups (taxa) from broadest to most specific Domain, Kingdom, Phylum, Class, Order, Family, Genus, species Domain, Kingdom, Phylum, Class, Order, Family, Genus, species

14 Hierarchy-Taxonomic Groups Domain Kingdom Phylum (Division – used for plants) Class Order Family Genus Species BROADEST TAXON Most Specific

15 Daring King Phillip Came Over For Gooseberry Soup!

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17 Taxons 17-2 Most genera contain a number of similar species Most genera contain a number of similar species The genus Homo is an exception (only contains modern humans) The genus Homo is an exception (only contains modern humans) evolutionary relationships Classification is based on evolutionary relationships

Determining Species Typological Species Concept – Looks at physical characteristics – Limited due to variation of alleles for traits Biological Species Concept – Looks at similarity in characteristics and the ability to breed fertile offspring – Limited due to not all separate species are unable to breed (i.e. wolves and dogs) Phylogenetic Species Concept – Looks at evolutionary history – Limited due to unknown histories for some species 18

19 Basis for Modern Taxonomy Homologous (morphological characters) structures (same structure, different function) Homologous (morphological characters) structures (same structure, different function) Similar embryo development Similar embryo development Molecular Similarity (biochemical characters) in DNA, RNA, or amino acid sequences in Proteins Molecular Similarity (biochemical characters) in DNA, RNA, or amino acid sequences in Proteins

20 Homologous Structures (BONES in the FORELIMBS) shows Similarities in mammals.

21 Similarities in Vertebrate Embryos

22 Cladogram Diagram showing how organisms are related based on shared, derived characteristics such as feathers, hair, or scales

As animals evolve, they derive new features, or characteristics. A derived characteristic can be any attribute of an animal, from the shape of its bones and muscles to its genetic chemistry and DNA.

+/- Table 0/1 Table Cladogr am

25 Primate Cladogram

26 Dichotomous Keying Used to identify organisms Used to identify organisms Characteristics given in pairs Characteristics given in pairs Read both characteristics and either go to another set of characteristics OR identify the organism Read both characteristics and either go to another set of characteristics OR identify the organism

27 Example of Dichotomous Key 1a Tentacles present – Go to 2 1b Tentacles absent – Go to 6 2a Eight Tentacles – Octopus 2b More than 8 tentacles – 3 3a Tentacles hang down – go to 4 3b Tentacles upright–Sea Anemone 4a Balloon-shaped body–Jellyfish 4b Body NOT balloon-shaped - 5

1. a. wings covered by an exoskeleton ………go to step 2 b. wings not covered by an exoskeleton ……….go to step 3 2. a. body has a round shape ………. Coccinella septempunctata b. body has an elongated shape ………. Camnula pellucida 3. a. wings point out from the side of the body ………. Aeshna cyanea b. wings point to the posterior of the body ………. Musca domestica

Making a Dichotomous Key Tree Dichotomous Key 29

30 Broadest, most inclusive taxon Broadest, most inclusive taxon Three domains Three domains Archaea and Eubacteria are unicellular prokaryotes (no nucleus or membrane-bound organelles) Archaea and Eubacteria are unicellular prokaryotes (no nucleus or membrane-bound organelles) Eukarya are more complex and have a nucleus and membrane- bound organelles Eukarya are more complex and have a nucleus and membrane- bound organelles Domains 17-3

3 Domains

The Six Kingdoms AnimaliaPlantaeFungi Protista Eubacteria Archaebacteria Ancient common ancestor

33 ARCHAEA Probably the 1 st cells to evolve Live in HARSH environments Found in: – Sewage Treatment Plants – Thermal or Volcanic Vents – Hot Springs or Geysers that are acid – Very salty water (Dead Sea; Great Salt Lake)

34 ARCHAEAN

35 EUBACTERIA Some may cause DISEASE Found in ALL HABITATS except harsh ones Important decomposers for environment Commercially important in making cottage cheese, yogurt, buttermilk, etc.

36 Live in the intestines of animals

37 Domain Eukarya is Divided into Kingdoms Protista (protozoans, algae…) Protista (protozoans, algae…) Fungi (mushrooms, yeasts …) Fungi (mushrooms, yeasts …) Plantae (multicellular plants) Plantae (multicellular plants) Animalia (multicellular animals) Animalia (multicellular animals)

38 Protista Most are unicellular Most are unicellular Some are multicellular Some are multicellular Some are autotrophic, while others are heterotrophic Some are autotrophic, while others are heterotrophic Mostly Aquatic Mostly Aquatic

39 Fungi Multicellular, except yeast Multicellular, except yeast Absorptive heterotrophs (digest food outside their body & then absorb it) Absorptive heterotrophs (digest food outside their body & then absorb it) Cell walls made of chitin Cell walls made of chitin

40 Plantae Multicellular Multicellular Autotrophic Autotrophic Absorb sunlight to make glucose – Photosynthesis Absorb sunlight to make glucose – Photosynthesis Cell walls made of cellulose Cell walls made of cellulose

41 Animalia Multicellular Multicellular Ingestive heterotrophs (consume food & digest it inside their bodies) Ingestive heterotrophs (consume food & digest it inside their bodies) Feed on plants or animals Feed on plants or animals

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43 Classification is Fun!