1. Classification and Beyond Chapters 19

2. Why do we name things? To distinguish one thing from another To communicate with others more effectively It forces us to examine things more closely and make distinctions

4. Classical Taxonomy – the Binomial System Carl von Linné (a.k.a.) Carolus Linnaeus Binomial nomenclature – each organism gets two names, a genus name and a species name. These are always used together. You cannot use a species name without the genus name.

5. If you ordered americanus in a restaurant …. Homarus americanus – lobster Ursus americanus – black bear Bufo americanus – American toad

6. 3 Domains Archaea Eubacteria Eukarya

7. Kings Play Chess On Fine Grained Sand: Kingdom Phylum Class Order Family Genus Species Taxon - a group of organisms at any particular level in this system

8. Biological Species Concept Biological species are groups of actually or potentially interbreeding populations that are reproductively isolated from other such groups. Reproductive unit Genetic unit Ecological unit

9. Phenetics Based on observable characteristics Uses “yes or no” questions “numerical taxonomists” –Choice of characteristics is subjective –Groupings unrelated to evolution –Environment affects some characteristics more than others

10. Cladistics Produce evolutionary trees Groupings include the ancestral species and all its descendants – Monophyletic Uses physical characteristics, fossil record and sequences of proteins and genes Sometimes it agrees with classical taxonomy and sometimes it does not

12. DNA and protein sequencing Evolve the same way as other characteristics – homologous or analogous? Also involves subjective choices Noncoding DNA tends to change at a more constant rate – can be used as a “molecular clock.”