1. EVOLUTION

2. What is evolution?
Evolution is the process of gradual change through time
Whose name do you associate with the word evolution?

3. Charles Darwin

5. 1. the birds had a common ancestor
After years of studying these birds he concluded the following:
1. the birds had a common ancestor

6. 2. the finches had different niches in order to survive; they had different food sources and different places to live on the island

7. Based off the study of these finches, Darwin came up with the Theory of Natural Selection

8. The theory of natural selection states the following:
1. Every species has to compete for food and living space in order to survive

9. 2.organisms better adapted to the environment survive and reproduce more successfully than organisms not as well adapted

10. 3. reproduction leads to genetic variations
4. genetic variation prevents extinction

11. Comparative Studies
Scientist use different types of comparative studies to show that certain organisms have a common ancestor

12. Types of Comparative studies:
1. Comparative Anatomy The scientist compare skeletal structures of different vertebrates to see if they have a similar basic structure
The different types of structures are:

13. Homologous structures
Similar in structure; made up of the same type of bones
But have different functions

16. But different structure Examples: Wings of an insect and a bird
Analogous structure
Same function
But different structure
Examples:
Wings of an insect and a bird

18. Vestigial structures
Organs that have no useful function, but show evolutionary change
Examples:
Ear muscles
Wisdom teeth
Tail bone
Appendix
tonsil

20. 2. comparative cytology
Scientists compare cells and cell organelles of different groups

22. 3.comparative embryology: Comparisons of early embryonic stages of different organisms

23. Comparative embryology

24. 4. comparative biochemistry
Compares DNA or Amino Acid sequence to show evidence of common ancestry

27. 5. Gel Electrophoresis:

28. Gel Electrophoresis is a complex laboratory technique that is used to analyze DNA, RNA and proteins
Mixtures of DNA are cut with restriction enzymes and separated into different size pieces

29. The DNA pieces are then placed in structures called wells
An electric current is applied to the gel creating an electric field inside the gel
DNA pieces move towards the POSITIVE pole

30. The smaller fragments move faster and farther towards the POSITIVE pole
The DNA pieces form banding patterns in the gel
Organisms with similar banding patterns are more closely related

32. Phylogenetic tree [family tree]
A Phylogenetic tree is a diagram showing the evolutionary interrelations of a group of organisms that come from a common ancestor
The ancestor is in the tree “trunk”; organisms that have arisen from it are placed at the ends of tree “branches.”

33. The distance of one group from the other groups indicates the degree of relationship 
closely related groups are located on branches close to one another. 

39. `