Taxonomy The science of naming organisms.
Why Classify?
Aristotle Did It Plant or animal? If an animal, does it Fly Swim Crawl Simple classifications Used common names
Carolus Linnaeus did it better Father of modern classification Based his system on homologous structures Developed binomial nomenclature First word = genus name (capitalized) Second word = species name (not capitalized)
Why binomial nomenclature? Much easier than a 10+ word name under old polynomial system Same name no matter where you go Less confusion Names used to be Oak with deeply divided leaves that have no hairs on their undersides and not teeth around their edges.
Taxonomic hierarchy Names organisms and their relationships from very broad to very specific
Scientific Names You Need to Know Homo sapiens Canis lupus Felis domesticus Ursus arctos Ursus maritimus Ursus americanus
Record the taxa for Homo sapian: Domain- Kingdom - Phylum- Class- Order- Family- Genus- Species-
What is a species anyway? Species- A group of organisms that can reproduce and produce viable offspring How many are out there? Scientists currently estimate that There are 10 million species worldwide Over 5 million live in the tropics Most unnamed species are small or microscopic
Why is taxonomy useful? Helps prevent confusion among scientists Helps to show how organisms are related Can be used to reconstruct phylogenies evolutionary histories of an organism or group
Traditional vs Modern Taxonomy Linneaus (1700 s) Modern (2000 s) 2 Kingdoms (KPCOFGS) Based on homologous structures 3 Domains 6 Kingdoms (DKPCOFGS) Based on evolutionary relationships (DNA, proteins, embryology, fossil record, homologous structures
A note on cladograms Cladogram- diagram that show evolutionary relationships Graph showing when different groups diverged from a common ancestral line Points where they diverge are often noted with a feature that was different between ancestral group and a new feature in the group that split off.
Bird Cladogram
Classification vs. Cladogram
The 6 kingdoms Bacteria - 1.Eubacteria Archaea 2.Archaebacteria Eukaryotes 3.Fungi 4.Protista 5.Animal 6.Plantae
Overview of the 6 kingdoms Archaebacteria Unicellular Live in extreme environments Prokaryotic Eubacteria Unicellular Prokaryotic Common bacteria
Overview of the 6 kingdoms Protista Eukaryotic Unicellular or colonial Lots of different life styles Fungi Cell walls made of chitin Eukaryotic Multicellular External heterotrophs
Overview of the 6 kingdoms Plantae Eukaryotic & Multicellular Cell walls made of cellulose Autotrophic Animalia Eukaryotic & Multicellular No cell walls Internal heterotrophs
Vocab to review Taxonomy Classification Dom,King, Phyl, Class, Order, Family, Genus, Species Binomial Nomenclature Autotrophs/ Heterotrophs 6 Kingdoms- Eukaryotes/Prokaryote
Practice Questions 1. A tool often found in a field guide that is used to identify organisms is called a. Cladogram b. Binomial Nomenclature c. Dichotomous Key d. taxonomy
2. Organisms that eat other organisms for food are called. 3. The two part naming system developed by Linneus is called. 4. The geologic timeline covers a very long time, how far does the current timeline go back? (How old is the earth?)
5. Which of the following domain includes organisms that can be found in extreme temperatures of deep sea vents? a. Bacteria b. Eukarya c. Archae d. Animalia
6. Humans are a. Ingestive autotrophs b. Absorptive autotrophs c. Ingestive heterotrophs d. Absorptive heterotrophs
7. In Aristotole s system of classification, animals are grouped according to their a. Size b. Habitat c. Structrue d. ancestors
8. Unicellular eukaryotes belong to the kingdom? 9. Unicellular prokaryotes that are found in the back of your refrigerator are called? 10. Organisms that lack a nuclear membrane are called?