Examine the evolutionary basis of modern classification systems. 1 Classification of Living Organisims Classification is the grouping of objects based on similarities. Examine the evolutionary basis of modern classification systems. (six kingdoms)

2 Classification Classification is an important process in understanding how organisms are related and how they are different. Taxonomy is the branch of biology that studies the grouping and naming of organisms.

Aristotle Ancient Greece— 3 Aristotle (384 BC to 322 BC) was the first to use a classification system. classified living things into two categories: plants and animals. Plants -shrubs, herbs, or trees. Animals -according to where they lived. His classification system was based on structural differences that were seen.

classification on characteristics of organisms that were similar. 4 Carolus Linnaeus (1707-1778) Swedish Botantist Considered to be the Father of modern Taxonomy based his classification on characteristics of organisms that were similar. Developed the two word system used to identify species: binomial nomenclature.

5 Linnaeus used Latin for the Names of his categories, because this was the language of educated people and not likely to change whereas an everyday language is likely to change. Clip on next slide

Binomial nomenclature 6 Binomial nomenclature Because scientists speak many different languages and common names for organisms may vary from place to place, a universal system for naming organisms is used. The scientific name of an organism is based on a two-word system called binomial nomenclature.

Quercus alba: is the name for white oak (alba is Latin for “white”) 7 Quercus alba: is the name for white oak (alba is Latin for “white”) Quercus rubra: is the name for the red oak (rubra is Latin for “red”) Micropterus salmoides is the name for a largemouth bass

Binomial nomenclature 8 Binomial nomenclature The two words, genus and species, are always italicized (or underlined). The first word in a scientific name, genus, is always capitalized and the second word, species, is never capitalized. For example the scientific name of the largemouth bass would be Micropterus salmoides (or Micropterus salmoides).

9 In addition to (1) appearance and (2)behavior, (3) molecular structure (e.g., DNA) and(4) evolutionary relationships are also considered when classifying organisms. Organisms that share more similarities are more closely related and are grouped together.

Eight levels of classification 10 Eight levels of classification Domain Least alike Most alike

11 GROUP NAME ORGANISM HUMAN CHIMPANZEE HOUSE CAT LION HOUSEFLY KINGDOM Animalia PHYLUM Chordate Arthropoda CLASS Mammal Insect ORDER Primates Carnivora Diptera FAMILY Hominidae Pongidae Felidae Muscidae GENUS Homo Pan Felis Musca SPECIES sapiens troglodytes domestica leo Scientific Name Homo sapiens Pan troglodytes Felis domestica Felis leo Musca domestica

Example: Human Classification 12 Example: Human Classification Domain: Eukarya Kingdom: Animalia Phylum: Chordata Class: Mammalia Order: Primate Family: Hominidae Genus: Homo Specific : sapiens How would you write the scientific name? a. homo Sapiens b. Homo sapiens c. Homo Sapiens

CLASSIFICATION OF THE LARGEMOUTH BASS 13 CLASSIFICATION OF THE LARGEMOUTH BASS Domain Eukarya Kingdom Animalia (multicellular organisms that eat food) Phylum Chordata (animals with a backbone) Class Actinopterygii (ray-finned fishes) Order Perciformes (perch-like fishes) Family Centrarchida (sunfishes) Genus Micropterus (types of bass) Species salmoides (largemouth bass) Largemouth Bass: Micropterus salmoides

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15 KINGDOMS OF LIFE

Six Kingdoms of Life 16 Plantae Protista Animalia Fungi EuBacteria Archae-bacteria Fungi

Three Domains and Six Kingdoms: 17 Three Domains and Six Kingdoms: Three Domains: Bacteria- Unicellular and prokaryotic. Autotrophic and Heterotrophic. Cell walls have peptidoglycan. Kingdoms: Eubacteria Archaea- Unicellular and prokaryotic. Cell walls do not have peptidoglycan. Kingdoms: Archaebacteria Eukarya- Eukaryotic. Kingdoms: Protista, Plantae, Fungi, Animalia.

Bacteria Protista Fungi 18 Bacteria Protista Fungi Eubacteria (true bacteria) and Archaebacteria contain prokaryotes, cells without membrane-bound organelles. Microscopic & unicellular. Archaebacteria are mainly found in extreme environments like the deep oceans, hot springs, and swamps. Heterotropic and autotrophic unicellular and multicellular organisms with a variety of characteristics eukaryotic organisms that lack complex organ systems and live in moist environments. Heterotropic and autotrophic consumers that stay put. unicellular or multicellular heterotrophic eukaryotes that absorb nutrients from dead and decaying matter by decomposing dead organisms and wastes in the environment.

Multicellular eukaryotes that photosynthesize. 19 Plantae Animalia Multicellular eukaryotes that photosynthesize. Most have cellulose cell walls and tissues that have been organized into organs and organ systems. Autotrophic-some parasitic. Multicellular consumers-heterotrophic Cells do not have cell walls. Their tissues have been organized into complex organ systems; the nervous system, muscle system and digestive system, as well as others.

20 6 Kingdoms of Life

Kingdoms

Evolutionary relationship between the kingdoms. 21 Evolutionary relationship between the kingdoms. Clip

Phylogeny To classify species according to how they are related, scientists must look at more than just physical traits. Modern classification is based on evolutionary relationships. The evolutionary history of a group of species is called a Phylogeny. Phylogenics can be shown as branching tree diagrams.

Cladistics The most common method used to make evolutionary trees is called cladistics. Cladistics is classification based on common ancestry. A Cladogram is an evolutionary tree that proposes how species may be related to each other through common ancestors. The traits that can be used to figure out evolutionary relationships among a group of species are those that are shared by some species but are not present in others. These traits are called Derived Characteristics.

Cladogram

Species’ Relatedness Today, new technology allows biologists to compare groups of species at the molecular level. In many cases, molecular data agree with classification based on physical similarities. Ex: Based on physical traits, most biologists considered segmented worms and arthropods to be more closely related than other species. Through molecular comparisons they discovered that round worms, NOT segmented worms should be more closely related to arthropods. Why does DNA often have the “last word” when scientists are constructing evolutionary relationships?

Review E D F G B C A Which two species are most closely related (similar DNA sequences)? D & E And F &G

A tool to identify organisms is called a dichotomous key. 22 A tool to identify organisms is called a dichotomous key. It is made from pairs of contrasting characteristics (e.g., has wings/does not have wings).

Dichotomous Key Chart of paired statements used to identify an organism. Classifying into two opposite parts. For Example: 1a. Organism has hair or fur……………..Go to 2 1b. Organism does not have hair or fur….Go to 5

23 EOCT ALERT!!!! A multicellular organism that obtains its food by absorbing nutrients from the soil belongs to the kingdom A Animalia B Fungi C Plantae D Protista

The study of animals is known as 24 The study of animals is known as A botany B ecology C taxonomy D zoology

25 In 1988, the tiger swallowtail, Papilio glaucus, was proclaimed Georgia’s state butterfly. The tiger swallowtail shares the most characteristics with members of which taxonomic level? A class B family C order D phylum

A obtain energy B reproduce C move D exchange gases 26 One main difference between members of the Kingdoms Plantae and Animalia is the ability to A obtain energy B reproduce C move D exchange gases