1. Phylogenetic Trees/Cladistics Sticker: 1.If two species share many similar structures, this indicates that they are more (closely/distantly) related and have a more (recent/distant) last common ancestor. 2.A _________ structure, like the appendix, has lost most or all of its original function over evolutionary time. 3.If two species share a homologous skull ridge, this indicates what about shape of their last common ancestor’s skull? Sticker: 1.If two species share many similar structures, this indicates that they are more (closely/distantly) related and have a more (recent/distant) last common ancestor. 2.A _________ structure, like the appendix, has lost most or all of its original function over evolutionary time. 3.If two species share a homologous skull ridge, this indicates what about shape of their last common ancestor’s skull?

2. Homework

3. Recap  Variation + Inheritance + Overreproduction + Limited Resources = Reproductive advantage = more babies = natural selection. Change in allele frequencies over time = evolution.  Can increase OR decrease biodiversity, complexity  Cumulative effects of natural selection over many generations + barrier that limits gene flow -> Speciation  More recent last common ancestor = more related = more similar  Scientists can determine common ancestry by comparing morphology. They can use this information to make a cladogram, or diagram of common ancestry.  Identical structures  Homologous structures  Adult homologous structures  Adult vestigial structures  Embryo structures  Variation + Inheritance + Overreproduction + Limited Resources = Reproductive advantage = more babies = natural selection. Change in allele frequencies over time = evolution.  Can increase OR decrease biodiversity, complexity  Cumulative effects of natural selection over many generations + barrier that limits gene flow -> Speciation  More recent last common ancestor = more related = more similar  Scientists can determine common ancestry by comparing morphology. They can use this information to make a cladogram, or diagram of common ancestry.  Identical structures  Homologous structures  Adult homologous structures  Adult vestigial structures  Embryo structures

4. Objectives  Learn how to make and read a phylogenetic tree (or cladogram)  Learn how to put together cladograms and anatomy (homologous structures, vestigial structures, etc.) to determine descent  Learn how to make and read a phylogenetic tree (or cladogram)  Learn how to put together cladograms and anatomy (homologous structures, vestigial structures, etc.) to determine descent

5. “What Did T. Rex Taste Like?”  You’ll proceed through an online tutorial that will teach you what a phylogenetic tree is, how to read one, and how to make one.  Work two per laptop  Remember, this is how you’re going to learn this concept, I’m not going to stand up and give notes on it. Don’t click “Next” if you don’t understand what the screen is teaching you.  Concepts from before to remember:  You’ll proceed through an online tutorial that will teach you what a phylogenetic tree is, how to read one, and how to make one.  Work two per laptop  Remember, this is how you’re going to learn this concept, I’m not going to stand up and give notes on it. Don’t click “Next” if you don’t understand what the screen is teaching you.  Concepts from before to remember:

6. Instructions  Go to http://www.ucmp.berkeley.edu/education/ex plorations/tours/Trex/navigation.html http://www.ucmp.berkeley.edu/education/ex plorations/tours/Trex/navigation.html  Click “Go To Beginning”  Go through each of the folders in order.  Complete the handout, take any notes you’d care to on the main ideas.  THINK AND UNDERSTAND! ASK QUESTIONS WHEN CONFUSED!  Go to http://www.ucmp.berkeley.edu/education/ex plorations/tours/Trex/navigation.html http://www.ucmp.berkeley.edu/education/ex plorations/tours/Trex/navigation.html  Click “Go To Beginning”  Go through each of the folders in order.  Complete the handout, take any notes you’d care to on the main ideas.  THINK AND UNDERSTAND! ASK QUESTIONS WHEN CONFUSED!

8. Cladograms  (Not for a sticker, required) There is a cladogram on the board. Please write your answers in your notebook:  Which number marks the last common ancestor for:  1. A and D?  2. C and H?  3. H and G?  Which symbol marks the point where a skull ridge feature arose, if these species have a skull ridge:  4. Only I?  5. B, E, C, H, G, I?  6. If I and G both have a feature, does that mean that H must have it too?  (Not for a sticker, required) There is a cladogram on the board. Please write your answers in your notebook:  Which number marks the last common ancestor for:  1. A and D?  2. C and H?  3. H and G?  Which symbol marks the point where a skull ridge feature arose, if these species have a skull ridge:  4. Only I?  5. B, E, C, H, G, I?  6. If I and G both have a feature, does that mean that H must have it too?

9.  What are the essential cladogram ideas?  Lineage  Last Common Ancestor  Why Related = Similar  What are the essential cladogram ideas?  Lineage  Last Common Ancestor  Why Related = Similar

10. Cladograms

11. Molecular Similarities  We can research ancestry by analyzing molecular similarities just like we could by analyzing anatomical similarities.  Similar molecular (DNA, RNA, and amino acid) sequences = more recent common ancestor = more closely related  We can research ancestry by analyzing molecular similarities just like we could by analyzing anatomical similarities.  Similar molecular (DNA, RNA, and amino acid) sequences = more recent common ancestor = more closely related

12. Molecular Similarities  Demonstration  Whiteboards  Demonstration  Whiteboards

13. Molecular Similarities  Molecular evidence is extremely powerful in studying evolution.  In modern-day science, we study molecular similarities more often and with more power than we study fossils!  Many scientists argue that this is now the most powerful tool in our research arsenal.  Molecular evidence is extremely powerful in studying evolution.  In modern-day science, we study molecular similarities more often and with more power than we study fossils!  Many scientists argue that this is now the most powerful tool in our research arsenal.

14. Whale Evolution  Online activity  First, use a highlighter to make a cladogram the “old fashioned way” from amino acid sequences  Then, you will use the National Center for Biotechnology’s real software and protein sequences to analyze the ancestry of whales  Online activity  First, use a highlighter to make a cladogram the “old fashioned way” from amino acid sequences  Then, you will use the National Center for Biotechnology’s real software and protein sequences to analyze the ancestry of whales