1. Chapter 13 / 32

2. The Theory of Evolution by Natural Selection
Charles Darwin
Before Darwin:
Strong religious power
1800s Lamarck (scientists) believed that organisms change based on needs

3. What was Thought.. Later Proved Wrong

4. Topic 1: Darwin’s Mechanism for Evolution
1859 Charles Darwin developed theory of evolution
Decades of science observations & experiments
Struggled in life: parents, school, religion
Interest in natural science conflicted his parents values
1831 HMS Beagle voyage to S. America (5 years)
Found evidence that species change over time
Fossils
Influenced by Malthus (increase in human population Vs food)
Charles Lyell (earth geology is changing)

5. The HMS Beagle Galapagos Islands (off coast of Ecuador)
Species there were similar to mainland but not the same
“descent with modifications”
OR evolution!!
Studied many organisms
Turtles, Iguanas, Finches most popular

7. Evolution by Natural Selection
Darwin’s association with Malthus:
“Natural Selection”
Favorable traits are selected for by
NATURE NOT THE ANIMAL!!

8. Evolution by Natural Selection
This “selection” or favorable VS unfavorable CAUSES changing in a population
(EVOLUTION)
Organisms differ from place to place because their habitats change from place to place
Form ADAPTATIONS (selective advantage)

9. examples

10. Animal Mimicry!

11. Make 4 Post-its about the notes we took today!
Open Notes Pop Quiz!
Name a scientists that influenced Darwin’s theory of evolution? What did that scientist do?
What was the name of the most famous island Darwin traveled to during his voyage?
The favorable traits are selected by___________ for natural selection.
What is an adaptation?
Finished?
Make 4 Post-its about the notes we took today!

12. Darwin’s Theory of Evolution
Published in The Origin of Species
SERIOUSLY controversial (humans evolved from apes)
4 Major points to Evolution

13. 4 major points to Theory of Evolution
Variation exists within the genes of every population or species (random mutation)

14. 4 major points to Theory of Evolution
2. In a particular environment, some individuals of a population or species are better suited to survive and have offspring

15. 4 major points to Theory of Evolution
3. Over time, the traits that make certain individuals of a population able to survive and reproduce tend to spread in that population

16. 4 major points to Theory of Evolution
4. There is overwhelming evidence from fossils and many other sources that living species evolved from organisms that are extinct (EVOLUTION)

17. Tempo of Evolution Gradual change over long periods of time
Gradualism
Rapid change separated by periods of little or no change
Punctuated equilibrium

18. Anatomy and Development
Vestigial Structures: evidence of evolution, not used today
Homologous structures: share common ancestor because of structure NOT FUNCTION

19. Notes Quiz
What are the 4 points to Darwin’s Theory of Evolution? Give an example of each
What are the 2 tempos of evolution? Give an example of each
What is the difference between a homologous trait and a vestigial trait?

20. Do Now: Tigers Whales Turkeys Insects Humans
List any examples of evolution found in the following species
Tigers
Whales
Turkeys
Insects
Humans

21. NATURE selects the favorable traits!
Examples of Evolution
NATURE selects the favorable traits!
4 Factors that drive natural selection

22. Topic 2: 4 factors of Natural Selection
All populations have genetic variation

23. 4 factors of Natural Selection
2. The environment presents challenges to successful reproduction

24. 4 factors of Natural Selection
3. Individuals tend to produce more offspring than the environment can support (COMPETETION)

25. 4 factors of Natural Selection
4. Individuals that are better able to cope with environmental challenges tend to leave more offspring than those less suited to their environment

26. Examples of Evolution Antibiotic Resistance in Bacteria
Tuberculosis 1980s, new strains
Original drugs Isoniazid and Rifampin don’t work anymore
Pesticide Resistance in Insects
EID Emerging Infections Diseases!!

27. Re-Emerging Infectious Diseases

28. Topic 3: Examples of Evolution
Darwin’s Finches
31 specimens
9 with similarities except for beaks
Determined by availability of food supply
-Damp Year
Small narrow
-Dry Year Big thick

29. Formation of New Species
Occurs in stages to best “fit” environment
Divergence- differences between groups
Leads to formation of new species (speciation)
Formation of Sub-species
Different habitats  different needs difference in species
Maintaining New Species
Reproductive barriers
Timing, geography, physical traits

30. Review
Write this down
What are the reproductive barriers when maintaining a new species?
Geography, timing, physical traits
What are the 4 factors of Natural Selection
Adapt or die, competition, nature’s challenges, variation
Example of a vestigial trait?
Whale hip-bone
Example of homologous trait?
Bat wing, human arm

31. The Evolution of Man 32.3 (731-738)
Darwin theorized that humans evolved from primates (prosimians, monkeys, apes) because of certain traits
Grasping Hands cling to mothers, branches, food
Forward Eyes judge distance, depth perception
First primates evolved ~50 million yrs ago (MYA)

32. Non-Human Primates Monkeys & Apes ~36 MYA Monkeys Apes
Diurnal (sleep at night, active during day)
Detect predators & food
Monkeys
First primates with opposable thumbs
Apes
No tail, larger brains
DNA of chimpanzee is 95% identical to human DNA

33. Human Primates (Hominids)
Primates that walk upright on 2 legs = hominid species
5-7 MYA
Early hominids walked on all fours…why change?
“Lucy” is an Australopithecine afarensis
3 MYA
Increased brain size
Walked upright
~40lbs and 3.5 ft tall

34. Homo habilis, erectus, sapien
Homo habilis = “Handy man” 2MYA
Tools & speech
Homo erectus = “Upright man” 1.5MYA
Evolved in Africa and migrated to Asia
Homo sapien = “Wise man” ~200,000 yrs
Only surviving of the hominids
Modern day human species and genus

35. VIDEO!!!!!