1. March 3 rd, 2010  Warm Up Open to ch. 17 to follow along with lecture  Today Review Ch. 17 Lab  Homework Study for Ch. 17 exam on Friday

2. Classification Chapter 17 Table of Contents Section 1 Biodiversity Section 2 Systematics Section 3 Modern Classification

3. Section 1 Biodiversity Chapter 17 Objectives  Relate biodiversity to biological classification.  Explain why naturalists replaced Aristotle’s classification system.  Identify the main criterion that Linnaeus used to classify organisms.  List the common levels of modern classification from general to specific.

4. Section 1 Biodiversity Chapter 17 Classifying Organisms  Naturalists have invented several systems for categorizing biodiversity, which is the variety of organisms considered at all levels from populations to ecosystems.

5. Classifying Organisms  Biodiversity: the variety of all organisms at all levels from populations to ecosystems  Classify organisms based on similarity

6. Section 1 Biodiversity Chapter 17 Taxonomy  Taxonomy is the science of describing, naming, and classifying organisms.  Taxon is any group within a taxonomic system

7. Aristotle PlantsAnimals Stem DifferencesHabitat (air, land, water)

8. Aristotle  Aristotle’s classification system  did not adequately cover all organisms  use of common names was problematic Jellyfish

9. Section 1 Biodiversity Chapter 17 Taxonomy, continued  The Linnaean System  Carolus Linnaeus devised classifying organisms according to form and structure

10. Chapter 17 Classification Hierarchy of Organisms Section 1 Biodiversity

11. Chapter 17 Levels of Classification  Binomial Nomenclature  Linnaeus’s system assign3e each species a two-part scientific name genus name + species identifier Example: Homo sapiens.

12. Section 2 Systematics Chapter 17 Objectives  Identify the kinds of evidence that modern biologists use in classifying organisms.  Explain what information a phylogenetic diagram displays.  State the criteria used in cladistic analysis.  Describe how a cladogram is made.  Discuss how proteins and chromosomes are used to classify organisms.  Explain cladistic taxonomy, and identify one conclusion that is in conflict with classical taxonomy.

13. Section 2 Systematics Chapter 17 Phylogenetics  A modern approach to taxonomy is systematics, which analyzes the diversity of organisms in the context of their natural relationships.  When classifying organisms, scientists consider fossils, homologous features, embryos, chromosomes, and the sequences of proteins and DNA.

14. Section 2 Systematics Chapter 17 Phylogenetics, continued  A phylogenetic diagram displays how closely related a subset of taxa are thought to be.  Phylogeny Phylogeny

15. Section 2 Systematics Chapter 17 Phylogenetics, continued  Evidence of Shared Ancestry  Homologous features  Pattern of embryological development

16. Section 2 Systematics Chapter 17 Cladistics  Cladistics uses shared, derived characters as the only criterion for grouping taxa.  Shared: a feature that all members of a group have  Derived: a feature that evolved only within the group Example: bird feathers Derived Traits

17. Chapter 17 Cladogram: Major Groups of Plants Section 2 Systematics

18. Chapter 17 Cladistics, continued  Molecular Cladistics  Molecular similarities (such as similar amino acid or nucleotide sequences), as well as chromosome comparisons, can help determine common ancestry.

19. Section 2 Systematics Chapter 17 Cladistics, continued  Chromosomes  Analyzing karyotypes can provide more information on evolutionary relationships.

20. Chapter 17 Similarities in Amino Acid Sequences Section 2 Systematics

21. Chapter 17 Phylogenetic Diagram of Mammals Section 2 Systematics

22. Section 3 Modern Classification Chapter 17 Objectives  Describe the evidence that prompted the invention of the three-domain system of classification.  List the characteristics that distinguish between the domains Bacteria, Archaea, and Eukarya.  Describe the six-kingdom system of classification.  Identify problematic taxa in the six-kingdom system.  Explain why taxonomic systems continue to change.

23. Section 3 Modern Classification Chapter 17 The Tree of Life  Revising the Tree  The phylogenetic analysis of rRNA nucleotide sequences by Carol Woese led to a new “tree of life” consisting of three domains aligned with six kingdoms.

24. Section 3 Modern Classification Chapter 17 Three Domains of Life  The three domains are Bacteria, Archaea, and Eukarya.

25. Section 3 Modern Classification Chapter 17 Three Domains of Life, continued  Domain Bacteria  Domain Bacteria aligns with Kingdom Eubacteria, which consists of single-celled prokaryotes that are true bacteria.

26. Section 3 Modern Classification Chapter 17 Three Domains of Life, continued  Domain Archaea  Domain Archaea aligns with Kingdom Archaebacteria, which consists of single-celled prokaryotes that have distinctive cell membranes and cell walls.

27. Section 3 Modern Classification Chapter 17 Three Domains of Life, continued  Domain Eukarya  Domain Eukarya includes the kingdoms Protista, Fungi, Plantae, and Animalia.  All members of this domain have eukaryotic cells.

28. Chapter 17 Phylogenetic Diagram of Major Groups of Organisms Section 3 Modern Classification

29. Chapter 17 Six Kingdoms

30. Chapter 17 Kingdom and Domain Characteristics Section 3 Modern Classification

31. Concept Map Review