2. Classification of Organisms Section 1: Categories of Biological Classification Section 2: How Biologists Classify Organisms

3. Taxonomy Taxonomy is the science of naming and classifying organisms Binomial nomenclature- Linnaeus’ 2 word system (Genus species) Scientific name: honey bee Apis mellifera

4. Scientific Name 1st letter of Genus is capitalized 1st letter of species is lower case Name is usually written in italics Red Oak = Quercus rubra

5. Classifying Organisms 3 Domains (new ??) Prokaryotes - Archaea Bacteria Eukaryotes - Protist, Fungi, Plants, Animals Levels of Classification Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

6. What is a Species? Biological species - a group of natural populations that are interbreeding or that could interbreed and are reproductively isolated from other such groups (natural barriers - geography)

7. # of Species Some groups of species do not have barriers and can reproduce unlimitedly 1.5 million species identified in world today 5-10 million more are believed to be in the tropics alone (rainforests) New species identified regularly

8. Evolutionary History Phylogeny- system of classification based on similarities (evolutionary history) Convergent evol. Species evolve independently of one another, but have similarities due to similar habitat. Analogous characters- similarities that arise through convergent evolution

9. Evolutionary Systematics Claudistics- focus on sets of unique traits found in a group of organisms Phylogenic Tree- represents a hypothesis of evolutionary history that may be inferred b/c it wasn’t observed