2. The Biodiversity of Life on Earth Where did it all start? How do we keep it all straight?

3. By the end of this lesson you will be able to: Describe the origin of life on earth* Explain the Theory of Endosymbiosis* Describe the role and importance of a taxonomist Compare Linnaeus’ classification system with today’s Use AND design a cladogram (phylogenetic tree) *** = Not in this chapter, but need to know!!!!

4. Happy Birthday Earth!!!!! Atmosphere of hydrogen cyanide, carbon dioxide, carbon monoxide, nitrogen, hydrogen sulfide, water vapor It was hot!!!!!

5. Then what??? 4 BYA the earth cooled forming solid rock 3.8 BYA the water remained in liquid form 3.5 BYA prokaryotic ancestors arose Oh, but how!?!?!?! Stanley Miller’s hypothesis

6. Next….. 2.2 BYA Oxygen gas became part of the atmosphere (photosynthesis) 2 BYA Eukaryotic ancestors arose from these How???

7. Endosymbiotic Theory What is going on here? –What did we start with? –What is the end product?

8. And then? Eukaryotic cells began sexual reproduction speeding up evolution Multicellular life began in the sea ~500 MYA the “Cambrian Explosion” occurred - diversification of life Today - More than 150 million species identified, leaving around 2-10 million yet to be discovered

9. How do we keep track of them all???? How do you keep track of your…. Classification - the science of taxonomy; allows us to use a common language

10. Carolus Linnaeus 18 th Century Swedish Botanist Classification system still used today Introduced binomial nomenclature –Two part Latinized name - italicized or underlined 1 st part - Genus - capitalized 2 nd part - species epithet - lower case Ex: Fundulus heteroclitus or F. heteroclitus Escherichia coli or E.coli

11. Linnaeus’s Classification System Hierarchal (levels) Starts out broad and gets specific Narrows it down to one organism Still used today, but slightly changed to reflect evolutionary relationships

12. Evolutionary Classification The study of phylogeny Groups organisms that have a common ancestor together

13. Cladogram/Phylogenetic Tree Groups organisms based on evolutionary relationships Uses shared derived characters - characteristics that arise over time and are shared by recent groups and not by the older groups

14. Cladogram Shared Derived Character

15. Classwork: 1) Construct a cladogram with the organisms in the table 2) Identify the organism that is least closely related to the others Shared Derived Character Chart OrganismsBackboneLegsHairs EarthwormAbsent TroutPresentAbsent LizardPresent Absent HumanPresent

16. Now, its your turn…. 1) Choose a category of objects or activities 2) Place them into different groups based on characteristics they share 3) Make a table, like the previous one to help arrange your groups 4) On one side of paper, Your table should include AT LEAST 5 different groups in the first column and 4 shared derived characters in the first row 5) On the other side, Design a cladogram using your approved chart. Give it a title, make it colorful, creative and easy to read!!!! It will be due…

17. Your Cladogram Use graph paper to complete your table and rough draft in-class now. Check your table with me and then start your rough draft on the back of the paper. Final draft due Wednesday April 6th.

18. Today’s Classification Using genetics to help us out!!! Similar genes = ??? More similar genes = a more recent common ancestor Genes used to eliminate confusion based on physical similarities alone

19. Molecular clock model DNA comparisons can be used to measure evolutionary time Relies on known mutation rates Used to estimate how long two species have been separated

20. Our Current System 3 Domains - Bacteria, Archaea, and Eukarya 6 Kingdoms - Eubacteria, Archaebacteria, Protista, Fungi, Plantae, and Animala Use graph paper and rulers to make and fill in the table for a reference sheet to be used for the next few chapters

21. Classification chart DomainsKingdoms Cell Type # of Cells Nutrition Mode Examples Bacteria Archaea Eukarya