1. Theory of evolution
Evolution is the changes that occur in organisms characteristics over time
Change in a species due to mutation of the DNA code that occurs over a long time

2. An example of Evolution

3. An example of Evolution

4. An example of Evolution

5. The Theory of Evolution by Natural Selection
Charles Darwin theory of evolution through natural selection is the most widely accepted theory

6. In 1831, Darwin set sail on the ship The Beagle, at age 22
In 1831, Darwin set sail on the ship The Beagle, at age 22 . He studied plant and animal life of the pacific islands and South America

7. Galapagos Island- observations of the animal and plant life here helped Darwin support his theory of Evolution through Natural Selection.

8. His greatest work came from his work with finches
                                                                                                                      
His greatest work came from his work with finches

9. 30 years after Darwin’s voyage he wrote a book The Origin of species by means of natural selection. (1859)
                                                                                          

10. None of these conclusions by Darwin have ever been disproved.
Natural Selection

11. Darwin’s theory of evolution through Natural Selection has 4 main concepts

12. All organisms tend to over reproduce.

13. In any population of organisms individuals will exhibit slight variation.

14. All organisms face a constant struggle for survival

15. Individuals with variations that are favorable for a particular environment are more likely to survive and pass on those favorable variations to the next generations

16. Gradually all offspring of the survivors will make up a larger proportion of the population. Over many years a population may come to look the same.

17. 4- Structural Similarities 5- Embryological Similarities
Evidence of Evolution
1-DNA sequencing
2- Fossil evidence
3-Adaptation
4- Structural Similarities
5- Embryological Similarities

18. Evidence of evolution
1-DNA sequence – by comparing the DNA patterns in organisms scientist can determine which organisms are closely related

19. Evidence of evolution
2-Fossils studying and observing fossils help determine how organisms have evolved

20. Plant Fossil Evidence:

21. EVIDENCE OF EVOLOTION 3-Adaptations: feautres suited to a particular environment that allow organisms to survive
Inuit people, who live in the extreme cold of the Arctic, have short, stout bodies that conserve heat.

22. Evidence of evolution
Masai people, who live in the arid lands of eastern Africa, have tall, lean bodies that disperse heat well.

23. Plant Adaptations: Venus Fly Trap Captures Animals Acquires Minerals
For Photo-
synthesis
Help!!!

24. Evidence of evolution
Embryological development- as the egg is fertilized the developing organisms show similar patterns of embryological development

25. Evidence of evolution
Anatomical similarities – similar body structures
Homologous structures- same origins-different functions
Analogous structures- different origins- same functions
Vestigial structures- no longer useful

26. Evidence of evolution
Structures on different organisms are homologous when they have similar base structures but have different functions.
Human Arm
Bat Wing
Whale Flipper

27. Evidence of evolution
Analogous structure- structures in different organisms that have the same functions and are different in structures. Probably had different ancestor ( origins) .

28. Results of Evolution by way of Natural Selection
Because of evolution the following results
A)    Organisms are strong and fit
B) Speciation occurs – new organisms are formed

29. Speciation How does Speciation occur? Geographic isolation
Divergent evolution
Convergent evolution
Gradualism
Punctual equilibrium

30. Geographic Isolation Separation of organisms by geographic features
Mountains
Lakes, oceans, rivers
Deserts
(May result in new species over time)

31. Gradualism
“gradual”
Small changes
Over a long time

32. Punctuated Equilibrium
“punctuation!”
Large changes
Happen rapidly
Periods of no change

33. Punctuated Equilibrium Gradualism:# S P E C I
Time

34. Divergent evolution- organisms that were similar in structure change and become a new species because the organisms changes to fit and survive in different environments

35. Divergence Original Species: Mammal Homologous structures Same origin
Human arm
“diverge”= branch off
Homologous structures
Same origin
Same underlying structure
Difference functions
Bat wing
Cat limb
Whale flipper
Original Species:
Mammal

36. Different origins but have same features
Convergent evolution organism that are different and unrelated change and develop similar body structures in order to survive in the environment
Different origins but have same features

37. Convergent Evolution
Placental mammals
Marsupial mammals