1. Evolution

2. What is Evolution? Evolution, or change over time, is the process by which modern populations have descended from preceding populations of organisms.

3. Who is Charles Darwin? Charles Darwin – born in England Charles Darwin – born in England Joined the crew of the Joined the crew of the H.M.S. Beagle Sailed around the world Sailed around the world Made numerous observations Made numerous observations and collected evidence that and collected evidence that led him to propose his led him to propose his hypothesis. hypothesis.

4. Darwin Malthus: Hutton & Lyell:Lamarck: Early scientists: past vs. present organisms ancient earth acquired traits population growth Natural Selection

5. What did Darwin observe during his voyage? Patterns of Diversity: Puzzled by distribution of different species (where they lived and did not live) Puzzled by distribution of different species (where they lived and did not live) He Asked (for example): He Asked (for example): * Why were there no rabbits in Australia, despite the * Why were there no rabbits in Australia, despite the presence of habitats that seemed perfect for them? presence of habitats that seemed perfect for them? * Why were there no kangaroos in England? * Why were there no kangaroos in England? * Why do they look so similar? * Why do they look so similar?

6. What did Darwin observe during his voyage? Living Organisms & Fossils Darwin collected and preserved fossils Darwin collected and preserved fossils Fossils: some resembled organisms that were still alive – others looked completely unlike any creature he had ever seen. Fossils: some resembled organisms that were still alive – others looked completely unlike any creature he had ever seen. He Asked: Why had so many of these species disappeared? disappeared? Looks LIKE a Kangaroo Looks nothing like any living species

7. What did Darwin Observe? The Galapagos Islands The Galapagos Islands Most influential place Darwin visited Most influential place Darwin visited Although islands were so close together, the islands had very different climates. Although islands were so close together, the islands had very different climates. Fascinated by the land tortoises, marine iguanas, & finches. Fascinated by the land tortoises, marine iguanas, & finches.

8. Where are the Galapagos Islands? A B C D CatchIT Question:

9. What did Darwin observe on the Galapagos Islands? Click to zoom into Galapagos Islands

10. What did Darwin observe on the Galapagos Islands? * Domed shell w/ short neck * Live on wetter islands * Have short necks that can reach grasses and vegetation on the ground Galapagos Tortoises

11. What did Darwin observe on the Galapagos Islands? * Flatter shell compared to domed * Live on slightly drier islands * Have longer necks than domed to reach short bushes and trees

12. What did Darwin observe on the Galapagos Islands? * “Saddle” w/ VERY long necks * Live on dry islands * Dry climates have less vegetation on the ground * Long neck used to reach vegetation up in bushes & trees growing off the ground

13. Galapagos Tortoises Click here for video

14. What did Darwin observe on the Galapagos Islands? All tortoises resemble a species living in South America All tortoises resemble a species living in South America Saw that giant tortoises varied in predictable ways from one island to another. Saw that giant tortoises varied in predictable ways from one island to another. The shape of a tortoise’s shell could be used to identify which island a particular tortoise lived. The shape of a tortoise’s shell could be used to identify which island a particular tortoise lived.

15. Natural Selection Questions (Bill Nye) 1. A young man that walked out was __ ___. 2. He quit medical school to become a ___. 3. How long did the Beagle stay in the Galapagos Islands? __ days 4. Finches had different shaped ___: varied by the environment they inhabited. 5. What was the mechanism that made evolution occur? ___ ____ 6. When did he publish his book? 7. Now, every where we look at today, we see something that came from ___.

16. Natural Selection Clip (Bill Nye) Click here for video Click here for video Click here for video Click here for video

17. Who influenced Darwin’s ideas? Recognized that Earth is many millions of years old. Recognized that Earth is many millions of years old. And the processes that changed Earth in the past are the same processes that operate in the present. And the processes that changed Earth in the past are the same processes that operate in the present. James Hutton and Charles Lyell (geologists)

18. Hutton and Lyell said… Volcanoes release hot lava and gases now, just as they did on an ancient Earth. Volcanoes release hot lava and gases now, just as they did on an ancient Earth. Erosion continues to carve out canyons, just as it did in the past. Erosion continues to carve out canyons, just as it did in the past. Also said that awesome geological features could be built up or torn down over long periods of time. (examples: earthquakes and volcanoes) Also said that awesome geological features could be built up or torn down over long periods of time. (examples: earthquakes and volcanoes) Wild/Crazy Idea: Earth changes over time

19. Hutton and Lyell So……Because of Hutton & Lyell’s work….. Darwin then asked: If the Earth could change over time, If the Earth could change over time, might life change as well? might life change as well?

20. Who else influenced Darwin’s Ideas? Malthus (an economist) – Studied population growth - observed that babies were being born faster than people were dying. Malthus (an economist) – Studied population growth - observed that babies were being born faster than people were dying. He reasoned that if the human population continued to grow unchecked, sooner or later there would be insufficient living space and food for everyone. He reasoned that if the human population continued to grow unchecked, sooner or later there would be insufficient living space and food for everyone.

21. Lamarck’s Theory of Evolution Proposed that by selective use or disuse of organs, organisms acquired or lost certain traits during their lifetime. These traits could then be passed on to their offspring. Over time, this process led to change in a species Who else was thinking about evolution? Was he “right”? Lets break it down….

22. How did Lamarck think organisms changed? Fiddler Crabs: An Example 1. The male crab uses its small front claw to attract mates and ward off predators 2. Because the front claw has been used repeatedly, it becomes larger (acquired). 3. A larger claw, is then passed on to the crab’s offspring. He was WRONG! He did not realize that the large claw traits were inherited

23. Lamarck’s Theory According to Lamarck's theory, a given giraffe could, over a lifetime of straining to reach high branches, develop an elongated neck, which would then be passed on to the next generation. The long neck is ACQUIRED Another Example:

24. What were Darwin’s arguments in his book? Natural Variation and Artificial Selection Argued that species were NOT perfect and unchanging. Argued that species were NOT perfect and unchanging. Natural Variation: There are differences Natural Variation: There are differences among individuals of a species. among individuals of a species.

25. What is Natural Variation? Peppered moths come in two versions White Version/Morph Black Version/Morph If trees in an area have dark bark, the black version blends in better and is less likely to be eaten by predators. If trees in an area have white bark, the white version blends in better and is less likely to be eaten by predators. Take home message: The natural variation may give certain members an advantage over others.

26. On the Origin of Species The actual title of his book is: The actual title of his book is: On the Origin of Species by Means of Natural Selection The book proposed a mechanism for evolution that he called natural selection. The book proposed a mechanism for evolution that he called natural selection. He presented evidence that demonstrates the process of evolution has been taking place for millions of years. He presented evidence that demonstrates the process of evolution has been taking place for millions of years. Darwin was 50 when it was published! Darwin’s Book

27. What is Natural Variation? BessieElsie * Elsie’s natural variation is to produce more milk than Bessie * Which cow would the farmer use to reproduce offspring? Why?

28. What were Darwin’s arguments in his book? Artificial Selection: Nature provided the variation among different organisms, and humans selected those variations that they found useful. * Only the largest hogs, fastest horses, and the cows that gave the most milk were selected to breed and produce offspring.

30. Darwin’s Evolution by Natural Selection The Struggle for Existence: members within each species compete regularly to obtain food, living space, and other necessities of life. The Struggle for Existence: members within each species compete regularly to obtain food, living space, and other necessities of life. A predator that is the fastest or has a specialized way of catching prey can catch more prey. A predator that is the fastest or has a specialized way of catching prey can catch more prey. Prey that are faster, better Prey that are faster, better camouflaged, or better protected camouflaged, or better protected avoid being caught. avoid being caught.

31. Darwin’s Evolution by Natural Selection Survival of the Fittest: Process by which individuals that are better suited to their environment survive and reproduce most successfully; also called Natural Selection. Survival of the Fittest: Process by which individuals that are better suited to their environment survive and reproduce most successfully; also called Natural Selection. Darwin called the ability of an individual to survive AND reproduce in its specific environment fitness. Darwin called the ability of an individual to survive AND reproduce in its specific environment fitness. An adaptation is any inherited characteristic that increases an organism’s chance of survival. An adaptation is any inherited characteristic that increases an organism’s chance of survival.

32. Darwin’s Discoveries Video Clip

33. Survival of the Fittest The concept of fitness, Darwin argued, was central to the process of evolution by natural selection. The concept of fitness, Darwin argued, was central to the process of evolution by natural selection.Example: Baby birds compete for food in the nest. The stronger bird may take food from the weaker siblings. Then…how is this related to fitness?

34. Evolution by Natural Selection Descent with Modification: Concept that each living species has descended, with changes, from other species over time. Implies that all living organisms are related to one another. Implies that all living organisms are related to one another. Common Descent: The principle that says all species – living and extinct – were derived from common ancestors.

35. Evidences of Evolution There are 4 categories

36. Evidence #1: FOSSIL RECORD

37. What are some evidence of Evolution? Fossil Record Fossils that had formed in the different layers of rock were evidence of gradual change over time. One could view how a species had changed and produced different species over time.

38. Evolution of Horses - - Horses do not look the same as they did many years ago - Fossil Record shows evidence that animals have changed over time and that they share common ancestors based on similarities in their skeletons.

39. Evidence #2: COMPARATIVE ANATOMY

40. Homologous Structures: Structures that have different mature forms in different organisms but develop from the same type of embryonic tissues. What are some evidences of Evolution? These structures provide evidence for common ancestry and evolution.

41. Vestigial Structures Vestigial Structures are structures that are the reduced forms of functional structures in different species. Vestigial Structures are structures that are the reduced forms of functional structures in different species. Examples: 1. Snake Pelvis: The pelvis is the attachment point for legs and is therefore nonfunctional in an animal without legs

42. Vestigial Structures 2. Kiwi Wing: The wings of kiwis are too small to be of any use in flight 3. Human Appendix: Important for digestion in many mammals, but of limited use in humans & some apes

43. Analogous structures can be superficially similar in construction, but are NOT inherited from a common ancestor. Analogous structures can be superficially similar in construction, but are NOT inherited from a common ancestor. Example: The wing of an eagle & the wing of a insect have the same function (both enable the organism to fly) – but are constructed in different ways & from different materials. Example: The wing of an eagle & the wing of a insect have the same function (both enable the organism to fly) – but are constructed in different ways & from different materials. What are some evidence of Evolution?

44. * While analogous structures do not indicate close evolutionary relationships, they do show that functionally similar features can evolve independently in similar environments. What are some evidence of Evolution?

45. Evidence #3: COMPARATIVE EMBRYOLOGY

46. Similarities in Early Development In their early stages of development, chickens, turtles, and rats look similar, providing evidence that they shared a common ancestry. What are some evidence of Evolution?

48. Evidence #4: COMPARATIVE BIOCHEMISTRY

49. What we know… All cells rely on DNA to make proteins. Using new technologies, biologists are able to determine the amino acid sequences in proteins to determine evolutionary relationships among various species of organisms. The more closely related two species are, the greater the similarity in amino acid sequences of their proteins.

50. For example:

51. Evolution Video Click here for video clip: Click here for video clip: Darwin, the Beagle, and Finches: Darwin Discovers Evidence of Natural Selection

52. Types of Evolution There are 5 main types

53. Divergent Evolution: When two species move away from the traits that they share with a common ancestor as they adapt to their own environments Also called Adaptive Radiation… Produces homologous structures, And are more CLOSELY related!

54. Convergent Evolution: When two distinct species with differing ancestries evolve to display similar features. Produces analogous structures, And are NOT closely related! Sugar Glider: Flying Squirrel Australian marsupial A GA squirrel

55. **Coevolution** Coevolution Coevolution Pollenation Pollenation

56. Geographic Distribution of Living Species - Species now living on different continents had each descended from different ancestors. - Because some animals on each continent were living under similar ecological conditions, they were exposed to similar pressures of natural selection. They ended up evolving certain striking features in common… but are NOT related! This is called Convergent Evolution

57. Punctuated Equilibrium Evolution that has long periods of stability or “unchange” followed by short periods of rapid change.

58. Gradualism A change that is very slow over time. It’s hard to notice a difference over a short period of time…it is slow and gradual.

60. 5. Biological Resistance Some organisms obtain a mutation that makes them resistant to a toxin (antibiotic or pesticide). Overuse of antibiotics & pesticides create populations of “super bugs”. This is why you need to take your antibiotics for the entire time… You expose the bacteria to the toxin; but if you don’t kill them all (take all your medicine), then you “taught them” how to resist the antibiotic!

61. Explanation of how resistance happens: http://www.sumanasinc.com/scienceinfocus/sif_antibiotics.html Explanation of how bacteria transmit resistance: http://survivalrivals.org/the-x-bacteria/animation Resistance Video about antibiotic resistance: http://www.youtube.com/watch?v=W-WumllRPLI

62. Remember the graph…? Frequency of Phenotype Generic Bell Curve for Natural Variation in a Complex Trait 5. Other patterns of selection

63. Key Percentage of Population Birth Weight Selection against both extremes keep curve narrow and in same place. a. Stabilizing Selection a. Stabilizing Selection Low mortality, high fitness High mortality, low fitness Stabilizing Selection What good reasons can you come up with for this trend? Human babies that have a really low birth weight… Human babies that have a really high birth weight… 5. Other patterns of selection

64. In stabilizing selection, the bulk portion of the bell-shaped curve is favored; In stabilizing selection, the bulk portion of the bell-shaped curve is favored; The average phenotype is favored The average phenotype is favored

65. Directional Selection Food becomes scarce. Key Low mortality, high fitness High mortality, low fitness b. Directional Selection

66. In directional selection, the one side of the bell-shaped curve is favored; In directional selection, the one side of the bell-shaped curve is favored; The one extreme phenotype is favored over the other, over the average The one extreme phenotype is favored over the other, over the average

67. Disruptive Selection Largest and smallest seeds become more common. Number of Birds in Population Beak Size Population splits into two subgroups specializing in different seeds. Beak Size c. Disruptive Selection Number of Birds in Population Key Low mortality, high fitness High mortality, low fitness

68. In disruptive selection, both end portions of the bell-shaped curve are favored; In disruptive selection, both end portions of the bell-shaped curve are favored; Both extreme phenotypes are favored over the average Both extreme phenotypes are favored over the average

69. Adaptation: body parts, body coverings, or behaviors that help an organism survive its environment or reproduce more effectively

70. Adaptations: Mimicry : Adaptation in which one species evolves to resemble another species for protection or other advantages. Mimicry : Adaptation in which one species evolves to resemble another species for protection or other advantages.

71. Adaptations: Camouflage : Adaptation Camouflage : Adaptation that allows organisms to blend that allows organisms to blend into their surrounds. into their surrounds.

72. Adaptations: Imprinting: a form of learning in which a very young animal fixes its attention on the first object experience and then follows that object Imprinting: a form of learning in which a very young animal fixes its attention on the first object experience and then follows that object

73. Plants: Tropisms (Growth Responses): 1) Phototropism: Responds to light

74. Plants: Tropisms (Responses): 2) Thigmotropism: Responds to touch

75. Plants: Tropisms (Responses): 3) Gravitropism: Responds to gravity Click here for link to cool videos online. Click here for link to cool videos online.

76. Plants: Tropisms (Responses): 4) Hydrotropism: Responds to water

77. Cactus Ridges: Expand to store more water when it rains Thorns: Protect against being eaten No Leaves: Prevent water loss Waxy Covering: Prevent water loss Flowers: Can reproduce Sexually as well as asexually

78. Polar Bear Large Paws: Walking on snow Short/small Ears: Save Heat Long Claws: Catching prey/digging White/clear Fur: Blend in with snow Thick Blubber: Keep warm

79. Adaptation Prompt Draw an organism and describe the adaptations that make it “fit” (as in ‘fitness,’ ‘survival of the fittest’). 1.) Organism must be drawn, in color, & neat 2.) Must include background environment 3.) Must have at least 3 adaptations w/ explanation of advantage for survival/reproduction Not adaptations: How long they live, where they live, what they eat Adaptation examples: * Large paws, thick beak, bright colored feathers, skinny legs, large ears, sharp teeth, fur thickness…. Hint: Must be clearly related to survival or reproduction!!

80. Another example to demonstrate these selection patterns: http://bcs.whfreeman.com/thelifewire/ content/chp23/2302001.html

81. http://devour.com/video/the- evolution-of-life-on-earth/ http://devour.com/video/the- evolution-of-life-on-earth/

82. The End