1. Essential knowledge 1.B.1:
Organisms share many conserved core processes and features that evolved and are widely distributed among organisms today.

2. Structural and functional evidence supports the relatedness of all domains
Can you think of any evidences that support the claim that all living things are related?

3. Evidence #1: Major features of the genetic code are shared by all modern living systems

4. Evidence #2 DNA and RNA are carriers of genetic information through transcription, translation and replication.

5. Evidence #3: Metabolic pathways are conserved across all currently recognized domains.
Scientific study to support the claim. Have student read the article and discuss in class. Abstract is on the following slide
A second article supporting evidence #3

6. The Phylogenetic Extent of Metabolic Enzymes and Pathways José Manuel Peregrin-Alvarez, Sophia Tsoka, and Christos A. Ouzounis1 Computational Genomics Group, The European Bioinformatics Institute, EMBL Cambridge Outstation, Cambridge CB10 1SD, UK
Abstract
The evolution of metabolic enzymes and pathways has been a subject of intense study for more than half a century. Yet, so far, previous studies have focused on a small number of enzyme families or biochemical pathways. Here, we examine the phylogenetic distribution of the full-known metabolic complement of Escherichia coli, using sequence comparison against taxa-specific databases. Half of the metabolic enzymes have homologs in all domains of life, representing families involved in some of the most fundamental cellular processes. We thus show for the first time and in a comprehensive way that metabolism is conserved at the enzyme level. In addition, our analysis suggests that despite the sequence conservation and the extensive phylogenetic distribution of metabolic enzymes, their groupings into biochemical pathways are much more variable than previously thought.

7. Structural evidence supports the relatedness of all eukaryotes.
How similar are you to a banana?
Answer: Very closely related

8. Example 1: Cytoskeleton (a network of structural proteins that facilitate cell movement, morphological integrity and organelle transport)

9. Example 2: Membrane-bound organelles (mitochondria and/or chloroplasts)

10. Example 3: Linear chromosomes

11. Example 4: Endomembrane systems, including the nuclear envelope

12. Essential knowledge 1.B.2:
Phylogenetic trees and cladograms are graphical representations (models) of evolutionary history that can be tested.

13. Cladograms

14. Look at the cladogram at the right
Look at the cladogram at the right. What conclusions can be drawn about the relationship between humans and chimps?
Image courtesy of

15. How to read a Cladogram
This diagram shows a relationship between 4 relatives. These relatives share a common ancestor at the root of the tree.
Note that this diagram is also a timeline. The older organism is at the bottom of the tree.
The four descendents at the top of the tree are DIFFERENT species. This is called SPECIATION.
Stress that cladograms not only serve as a pictorial representation of lineage, but also as a snapshot in time.
Be sure to introduce the term SPECIATION. The four descendents are DIFFERENT species.
Image courtesy of

16. The event that causes the speciation is shown as the fork of the “V”.
Branches on the tree represent SPECIATION, the formation of a new species.
The event that causes the speciation is shown as the fork of the “V”.
Image courtesy of

17. Species B and C each have characteristics that are unique only to them.
But they also share some part of their history with species A. This shared history is the common ancestor.
Image courtesy of

18. Write a sentence that summarizes the relationship between A and B
Write a sentence that summarizes the relationship between A and B. What is the only thing A and B have in common?
Be sure to have students justify their answer to the question.
Image courtesy of

19. A CLADE is a group of organisms that come from a common ancestor.
If you cut a branch of the tree, you could remove all the organisms that make up a CLADE.
Students should be able to decide if a group of organisms form a clade.
Image courtesy of

20. 3 Groupings

21. Bozeman - Cladograms Wg