1. Natural Selection and Evidence to Support Evolution
ACADEMIC ninth grade science

2. Natural Selection Darwin’s Mechanism for Evolution
Overproduction
Inherited variation
Struggle to survive
Successful reproduction
Adaptation of the species

3. Overproduction Too many offspring produced
Many variations -Gene Pool: the total of all alleles (variations) in population
-What is the allele frequency for feather color for this gene pool?

4. 2. Inherited Variation Mutation and random mating make variations
-Mutation: Changes in DNA ****(Darwin was missing this) -Random mating: mixing genes in reproduction
Most birds are blue
Sometimes, one is born green
Sometimes, one is born blueish-green

5. 3. Struggle to Survive Organisms compete for resources (food, shelter, mates, etc.)
Those with better variations survive

6. The birds face the challenge of blending in to survive.

7. Only some will survive and have the opportunity to pass on their successful genes.
Ugh!, so full…
EEP!
Blue-green birds stand out more
Blue-green birds are eaten

8. 4. Successful Reproduction Successful traits are passed to offspring
-More organisms with the successful trait -Fewer organisms with the less successful trait(s)
How has the allele frequency changed in this population?
This is evolution!

9. 5. Adaptation of the Species Adaptation: process by which a species becomes better suited to its environment ?
Hee, hee…

10. Warm up…
1. Use the diagram and explain the process of natural selection.

11. Pace of Evolution GRADUALISM: Slow Even pace PUNCTUATED EQUILIBRIUM:
Quick bursts
Many periods of no change

12. WoolyBooger…

13. Warm up…
Read the article on your sheet and begin to answer the questions on the back.

14. How does the WoolyBooger show NATURAL SELECTION?

15. Examples: Sickle cell Anemia Peppered Moth

16. Evidence to Support Evolution

17. 1. Fossils Any trace of a dead organism
Calcium in bones is replaced with harder elements
Soft tissues don’t often fossilize
Age determined by radiometric dating

18. Fossil Activity

19. Warm up… A
Make FOUR observations (facts) about these fossil footprints. Consider size, shape, & position.
Make FOUR inferences (educated guesses) about the prints that reconstruct the events that may have caused this pattern. There is more than one possible answer. B C

20. 2. Comparative Embryology
Vertebrates have similar early stages; gill slits, “fins”, a tail
Differences accumulate as development continues
New development instructions are added to old instructions inherited from ancestors.

21. 2. Comparative Embryology

22. 3. Transitional Forms Intermediates between old and new species
Ex: modern horse descended from dog-sized animal with multiple toes

23. Transitional Forms Fish to Amphibians

24. Transitional Forms Reptiles to Birds

25. Transitional Forms Land Mammals to Aquatic Mammals

26. Transitional Forms Activity
Turn to pages in the GREEN textbook.
Read about the transitional forms of the whale.
In your notes, describe what scientists think the ancient ancestor the modern whale was like.

27. NOW… Watch the Sickle Cell Anemia Video
Read the Sickle Cell Anemia Article
Use the information to complete the FRONT of the Natural Selection Examples sheet

28. Warm up… Watch the Peppered Moth video
Complete the BACK of the Natural Selection Examples sheet you received yesterday
(We will do antibiotic resistance in another class period)

29. 4. Homologous Structures
Structures with a common ancestry
Modified versions of structures from other organisms
Ex: bones in appendages

30. 4. Homologous Structures

31. 5. Vestigial Structures Structures with no present function
Remnants of the past;
Previously served a function
Ex: human appendix-may once have been used for digestion
Ex: whale’s pelvis-not needed for swimming, is needed for walking

32. 5. Vestigial Structures

33. Warm up… Take out the sheet from Friday
Complete the chart and questions with your partner, using the packet on the table

34. Which is NOT homologous & Why?A
Human
Lizard
Octopus B
Bird
Whale
Grasshopper
Lizard
Human

35. 6. DNA and Proteins DNA make an organism’s proteins
DNA sequence holds the evolutionary history
If species changes, their DNA changes
Closely related organisms share more similar DNA
Ex: humans and chimps share 98% DNA

36. 6. DNA and Proteins Human-Human=99.5% similar
Human-Chimpanzee=98% similar
Human-Cat=90% similar
Human-Cow=80% similar
Human-Mouse=75% similar
(90% analogous regions)
Human-Chicken=60% similar
Human-Fruit Fly=60% similar

37. DNA and Proteins Activity
Cytochrome C article???????

38. So…evolution can cause speciation
Speciation: formation of a new species as a result of natural selection

39. Madagascar & Speciation

40. Now… Read about Antibiotic Resistant Bacteria.
Answer the questions on the back of the Natural Selection Examples Sheet

41. Warm up…
1. Use the diagram and explain the process of speciation.

42. Antibiotic Resistance

43. Now…
Find your new group
Complete Speciation
Work time

44. Warm up…
Did any individual Peppered moth change its color during its lifetime?
Why? (or why not?)
Explain the change from light colored to dark colored moths.
36:15

45. Now… Quick Check-15 minutes-you know it or you don’t
Peppered Moth Graph
This MUST be finished TODAY
Graded TODAY and returned for the questions TOMORROW
Work time

46. Warm up…
What is the difference between an independent variable and a dependent variable?
Explain the steps of Natural Selection.
How does antibiotic resistance show natural selection?

47. Check yours… X Transitional Vestigial DNA Fossils Embryology
Homologous
Transitional
Vestigial
Embryology
DNA
Fossils
Gill Slits… X
Forelimbs…
DNA…
Archaeopteryx…
Whale pelvis…
Common ancestor…
Modern horse…

48. Check yours…
2. UNDERLINE each of these terms or ideas (not the descriptions)
Overproduction
Inherited variation
Struggle to survive
Successful reproduction
Adaptation of the species

49. Check yours… 3. CIRCLE your example
Underline each piece of natural selection you used to defend it