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End of Year Review Geologic Evidence of Change Over Time Wake County 8 th Grade Science Curriculum.

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1 End of Year Review Geologic Evidence of Change Over Time Wake County 8 th Grade Science Curriculum

2 Change Over Time Geologic Evidence Fossil: evidence of past life preserved in rock; Different kinds of fossils are: 1.Petrified fossil: minerals replace all or part of an organism You can see the rings. en.wikivisual.com

3 Change Over Time Geologic Evidence Mold: a hollow area in sediment in the shape of an organism or part of an organism; formed when the organism makes an indentation that turns to rock over time Cake mold

4 Change Over Time Geologic Evidence Cast: a solid copy of the shape of an organism; made by filling in a mold with minerals that later turn to rock. MoldCast esp.cr.usgs.gov

5 Change Over Time Geologic Evidence Carbon film: an extremely thin coating of carbon on rock; made when an organism is squeezed by rock until only carbon remains

6 Change Over Time Geologic Evidence Trace fossil: evidence of activities of ancient organisms; may be tracks, burrows, nest, or trail Fossil burrowFossil tracks igs.indiana.edu

7 Change Over Time Geologic Evidence Amber: a hardened resin, or sap, of evergreen trees; organisms that get trapped in the sticky substance becomes part of the rock pixdaus.co m

8 Change Over Time Geologic Evidence Frozen remains: organisms caught in ice or snow Adult mammoth flickr.com Frozen baby mammoth

9 Change Over Time Geologic Evidence Fossil record: the complete body of fossils that shows how species and ecosystems change over time images.mooseyscountrygarden.com anthropology.net

10 Change Over Time Geologic Evidence How do fossils give us the age of organisms that lived in the past? Is this fish fossil a few thousand years old or a few billion years old?

11 Change Over Time Geologic Evidence Dating Rocks and Fossils Relative Dating: uses information about rock layers and the fossil record to determine the age relationships between rocks Absolute Dating: any method of measuring the age of an event or object in years

12 ESSENTIAL QUESTION #1 What is the Law of Superposition?

13 Change Over Time Relative Dating Law of Superposition: states that the oldest rocks lie on the bottom and the youngest rocks are on top of any undisturbed sequence of sedimentary rocks. media-2.web.britannica.com

14 Which can most likely be concluded about the top layer of rock seen in an undisturbed cliff wall? A.The top layer is older than layers located farther down the cliff. B.The top layer is younger than layers located farther down the cliff. C.The top layer contains more fossils than layers located farther down the cliff. D.The top layer contains fewer fossils than layers located farther down the cliff.

15 Which can most likely be concluded about the top layer of rock seen in an undisturbed cliff wall? A.The top layer is older than layers located farther down the cliff. B.The top layer is younger than layers located farther down the cliff. C.The top layer contains more fossils than layers located farther down the cliff. D.The top layer contains fewer fossils than layers located farther down the cliff.

16 Change Over Time Relative Dating The fossils in layer 3 are “relatively” the same age. Which layers are older than layer 3? Which layers are younger than layer 3? 1 and 2 4,5,6,and 7

17 ESSENTIAL QUESTION #1 What is the Law of Superposition? Law of Superposition: states that the oldest rocks lie on the bottom and the youngest rocks are on top of any undisturbed sequence of sedimentary rocks.

18 Based on the Law of Superposition, what can be concluded about fossils? A.Fossils give clues about the past climate patterns. B.Fossils form from the hard parts of organisms. C.The oldest fossils are found in the lowest rock layers. D.The most recent fossils were advanced organisms.

19 Based on the Law of Superposition, what can be concluded about fossils? A.Fossils give clues about the past climate patterns. B.Fossils form from the hard parts of organisms. C.The oldest fossils are found in the lowest rock layers. D.The most recent fossils were advanced organisms.

20 ESSENTIAL QUESTION #2 How can an unconformity be used as evidence for geologic evolution?

21 Change Over Time Relative Dating Since the top of layer 5 and layer 6 are at the same level, are these two layers the same age? Why or why not?

22 Change Over Time Relative Dating No, they are not the same age. Layer 5 is older than layer 6. Unconformity: gaps in the rock record created when older rock is worn away then new rock is layered over it. You can see that parts of the older layers are missing.

23 ESSENTIAL QUESTION #2 How can an unconformity be used as evidence for geologic evolution? An unconformity can be used to determine relative age of rock layers.

24 Which does a scientist most likely consider when studying the relative ages of rock layers in a canyon wall? A.Chemical weathering B.Current climate C.Amount of daily rainfall D.Law of Superposition

25 Which does a scientist most likely consider when studying the relative ages of rock layers in a canyon wall? A.Chemical weathering B.Current climate C.Amount of daily rainfall D.Law of Superposition

26 ESSENTIAL QUESTION #3 How is the age of the earth determined?

27 Change Over Time Absolute Dating When magma or lava hardens, new rock is formed. When new rock is formed, some elements’ isotopes are radioactive.

28 Change Over Time Absolute Dating Isotope: an atom that has the same number of protons (or the same atomic number) as other atoms of the same element do but that has a different number of neutrons (thus a different atomic mass) Parent isotope: an atomic nucleus that is undergoing decay (Tritium H-3) Daughter isotope: the stable isotope that results from radioactive decay (Helium-3)

29 Change Over Time Absolute Dating Tritium is radioactive. It “decays” by losing an electron from one of the neutrons. Radioactive decay: the process in which a radioactive isotope tends to break down into a stable isotope of the same element or another element. The neutron becomes a proton increasing the atomic number from one (Hydrogen) to two (Helium) Parent isotope Daughter isotope

30 Change Over Time Absolute Dating Half-life: the time needed for half of a sample of radioactive substance to undergo radioactive decay (Tritium has a half-life of 12.5 years)

31 Change Over Time Absolute Dating

32 Change Over Time Absolute Dating All radioactive elements have a specific half-life library.thinkquest.org

33 Change Over Time Absolute Dating After measuring the amount of parent isotopes and daughter isotopes in a rock, scientists use mathematical calculations to determine the rock’s age. These calculations are based on the half-life of the isotopes. When the rock is dated, we can know exactly how long ago the organism was alive.

34 Change Over Time Absolute Dating Radioactive Dating: the process by which the age of a rock is determined by measuring the amount of radioactive isotopes present in the rock or rock sample eapbiofield.wikispaces.com

35 ESSENTIAL QUESTION #3 How is the age of the earth determined? Radioactive dating of Earth and moon rocks (4.6 billion years old).

36 ESSENTIAL QUESTION #4 How has the geology of the Earth changed over time?

37 Continental Drift Continental Drift Theory: theory that states that the gradual shifting of Earth’s plates causes continents to change their global positions over time. 37

38 38

39 Plate Tectonics Correlation: the matching up of rock layers from different locations Can use minerals in rock layers or fossils 39 physics.uwstout.edu

40 ESSENTIAL QUESTION #4 How has the geology of the Earth changed over time? Continents have moved because of the plates.

41 ESSENTIAL QUESTION #5 How has the Earth been impacted by major geological events?

42 42 Which is the best evidence that two continents were once connected? A.They have similar types of rocks and fossils. B.They are in the same stage of succession. C.They exist along the same line of latitude. D.They have the same climate.

43 43 Which is the best evidence that two continents were once connected? A.They have similar types of rocks and fossils. B.They are in the same stage of succession. C.They exist along the same line of latitude. D.They have the same climate.

44 Plate Tectonics Plate tectonics is the theory that explains how large pieces of the Earth’s outermost layer called tectonic plates move and change shape 44

45 Plate Tectonics Cause of Plate Movements: Heat from the core sets up convection currents within the mantle. As the mantle moves, it moves the plates above. 45 mediatheek.thinkquest.nl

46 Plate Tectonics All Over the World 46 cimss.ssec.wisc.edu

47 ESSENTIAL QUESTION #5 How has the Earth been impacted by major geological events? Plate tectonics has caused continents to move to different climates. Movement of plates cause mountains to build, earthquakes, and volcanoes. What other major geological events can you think of?

48 ESSENTIAL QUESTION #6 How have mechanical and chemical weathering impacted the earth?

49 Weathering 49 Mechanical weathering: is the erosion of rocks and soil caused by wind, water, or ice freezing inside rocks soilerosion.net WIND  WATER  WATER FREEZING 

50 50 Weathering Chemical weathering: is the erosion of rocks and soil caused by chemical reactions Iron in rock combining with oxygen to form iron oxide (rust) Pollutants causing acid rain that will react to minerals in natural rock or statues carved from rock edutel.musenet.org mail.colonial.net

51 51 Weathering Mountains formed by plate tectonics are constantly being worn down by mechanical and chemical weathering. The Himalayas are the largest mountains on Earth. The Appalachian Mountains used to be as large as the Himalayas. The Appalachians are now just the worn remnants of a once immense mountain range.

52 ESSENTIAL QUESTION #6 How have mechanical and chemical weathering impacted the earth? Mountains and other land features are worn down.

53 53 Which process best explains how mountain ranges are worn down over time? A.Asteroid impacts B.Volcanic eruptions C.Mechanical and chemical weathering D.Continental drift and seafloor spreading

54 54 Which process best explains how mountain ranges are worn down over time? A.Asteroid impacts B.Volcanic eruptions C.Mechanical and chemical weathering D.Continental drift and seafloor spreading

55 ESSENTIAL QUESTION #7 How have technological processes allowed us to understand change over time?

56 ESSENTIAL QUESTION #8 How does remote sensing help scientists make predictions about land use, urban sprawl, and/or resource management ?

57 Remote Sensing 57 Using satellites to study changes in Earth

58 58 Remote Sensing Satellite pictures/maps can be used to monitor land use, urban sprawl and resource management.

59 ESSENTIAL QUESTION #8 Why do scientists use remote sensing when monitoring the Earth? To see the change of Earth’s surface over time

60 ESSENTIAL QUESTION #9 How does the spectral analysis of reflectance curves help scientists monitor the Earth?

61 Spectral Analysis 61 The Gulf Stream can be seen (red) in this thermal satellite image Spectral analysis uses bands of reflected light to monitor changes in the Earth

62 ESSENTIAL QUESTION #9 How does the spectral analysis of reflectance curves help scientists monitor the Earth? It aids scientists by helping them get a visual picture of the atmosphere and surface that couldn’t be viewed otherwise.

63 ESSENTIAL QUESTION #10 How does ground truthing help scientists make predictions about land use, urban sprawl, and/or resource management?

64 Ground Truthing 64 When scientists study satellite images, they sometimes must go to the areas to see how the image correlates with the actual environment. ian.umces.edu

65 ESSENTIAL QUESTION #10 How does ground truthing help scientists make predictions about land use, urban sprawl, and/or resource management? This process lets them observe up close, what satellites have shown them.

66 ESSENTIAL QUESTION #7 How have technological processes allowed us to understand change over time? Satellite imagery has made it easier to observe plate tectonics. Machines can dig deeper to study rock layers. Can you think of others?

67 ESSENTIAL QUESTION #11 What evidence is there for climate change?

68 Global Change Due to fossil fuel use and other pollutants, the amount of CO 2 has been increasing steadily. earthobservatory.nasa.gov

69 Global Change Even though we have not experienced huge increases in temperatures, evidence of global warming is the melting of the polar ice caps. globalwarmingsiren.com

70 South Florida is home to millions of people...  This is what Florida would look like if all ice on this planet melted.  What would happen to the temperature if all ice on the planet were gone?

71 ESSENTIAL QUESTION #11 What evidence is there for climate change? Melting icecaps, sea level rising, slight global temperature increases.

72 ESSENTIAL QUESTION #12 What does the Geologic Time Scale tell us about the Earth’s geologic history and the evolution of life?What does the Geologic Time Scale tell us about the Earth’s geologic history and the evolution of life?

73 73 Geologic Time Scale The standard method used to divide the Earth’s long natural history into manageable parts geomaps.wr.usgs.gov

74 74 Geologic Time Scale Eon: largest division of geologic time Era: A unit of geologic time that includes two or more periods Period: a subdivision of the eras in geologic time Epoch: A subdivision of a geologic period Divisions are determined by the major life forms of the time

75 ESSENTIAL QUESTION #12 What does the Geologic Time Scale tell us about the Earth’s geologic history and the evolution of life? The four eras of the geologic time scale were set up based on the life of the era. Precambrian – Bacteria and small multi- celled organisms Paleozoic – Fish and arthropods Mesozoic – Reptiles Cenozoic – Mammals

76 ESSENTIAL QUESTION #13 How has the distribution of living things changed over time?

77 77Precambrian Longest time division 4.6 billion to 544 million. This is equal to a little more than 4 billion years. Early Earth: Geological Changes Water condensed and formed oceans Storms dominated the atmosphere Atmosphere was methane, ammonia, and other chemicals No oxygen Moon was closer so appeared larger

78 78 encarta.msn.com

79 79 Precambrian Considered the Age of Algae Biological Changes Simple single celled bacteria evolve in the oceans. Some bacteria adapt to photosynthesize and evolve into algae The atmosphere began to build up oxygen Some bacteria adapt to use oxygen in respiration Some cells form simple colonies Colonies of cells begin to evolve into small invertebrates

80 80 Bacterial Colony

81 81 Volvox Colony Cells work together to move the entire colony using individual flagella Individual cells are connected like a primitive life form Small colonies form inside and become individual colonies when the large one dies and breaks open io.uwinnipeg.ca

82 82 End of the Precambrian Oxygen in the atmosphere Most life is single celled organisms All life exists in oceans These are stromatolites formed by build- up of blue-green algae

83 83 Paleozoic Era 544 to 245 million years ago Geologic Changes: Life is still found mostly in the oceans but some moves to the land. Shallow seas cover most of the land including North America Coral reefs develop Continents collide creating the Appalachian Mountains Pangaea forms

84 84 Paleozoic Era As you can see (  ), most of the East was under water in early Paleozoic 

85 85 Paleozoic Era Continents collide causing the Appalachian Mountains to form This causes sea shell fossils to be on the top of mountains 

86 86 Paleozoic Era Pangaea forms forms

87 87 Paleozoic Era Mesosaurus was a species that lived on Pangaea. Fossils of the reptile and other species were made. When Pangaea broke up, the fossils could still be found on the different continents proving they were once connected Megosauruswww.answers.com s.com

88 88 Which best explains why fossils of the same species of a reptile were discovered in South America and in western Africa? A.The reptiles evolved in both South America and Africa. B.The continents of South America and Africa were once joined. C.Land bridges connected the continents of South America and Africa. D.The reptiles could swim the distance between South America and Africa.

89 89 Which best explains why fossils of the same species of a reptile were discovered in South America and in western Africa? A.The reptiles evolved in both South America and Africa. B.The continents of South America and Africa were once joined. C.Land bridges connected the continents of South America and Africa. D.The reptiles could swim the distance between South America and Africa.

90 90 Paleozoic Era Biological Changes Great “explosion” of new species of invertebrates

91 ESSENTIAL QUESTION #14 How do index fossils help us understand life forms in the four major geologic eras?

92 92 Paleozoic Era Biological Changes Trilobites appear at the beginning of this era… …then disappear at the end making them an index fossil for the Paleozoic Era Index fossil is found in a narrow time range but widely distributed around the earth; used to date rock layers in any era.

93 ESSENTIAL QUESTION #14 How do index fossils help us understand life forms in the four major geologic eras? Index fossils, if found in a rock layer with other fossils, can help us determine the relative age of that layer and the other fossils in it.

94 94 Paleozoic Era Biological Changes First land plants appear First spiders and insects appear bleedingeyeballs.com

95 95 Paleozoic Era Biological Changes Considered the “Age of Fish” due to the evolution of fish from a worm-like creature to a fish with a jaw

96 96 Paleozoic Era Biological Changes Simple amphibians then reptiles evolve animals.howstuffworks.com

97 ESSENTIAL QUESTION #13 How has the distribution of living things changed over time? Evolved from simple, single- celled organisms to more complex organism (amphibians to reptiles)

98 98 Mesozoic Era 245 to 66 million years ago or about 180 million years Geologic Changes: Hot and dry climate Pangaea splits into individual continents Widespread volcanic activity due to the continents moving

99 99 Mesozoic Era Hot and dry climate

100 100 Mesozoic Era Pangaea splits

101 101 Mesozoic Era Biological Changes Species evolved quickly to take advantage of the land that hadn’t been occupied by many species Dinosaurs appear and evolve quickly com

102 102 Mesozoic Era Biological Changes First mammal appears as a small rat-like animal org

103 ESSENTIAL QUESTION #15 What types of catastrophic events have occurred over time?

104 104 Mesozoic Era Biological Changes End of the Mesozoic Era ends with the sudden extinction of all dinosaurs One theory is that a comet hit the earth causing a cloud to cover the earth for years

105 105 Which most likely happened to species that are found in the fossil record but have no living members? A. They had offspring of a different species. B. They mutated to other species. C. They became extinct. D. They never really existed.

106 106 Which most likely happened to species that are found in the fossil record but have no living members? A. They had offspring of a different species. B. They mutated to other species. C. They became extinct. D. They never really existed.

107 107 Cenozoic Era Age of Mammals 66 million years ago to present Geologic Changes: Rocky Mountains and Himalayas form Ice ages periodically cover much of the land Last ice age ends

108 108 Cenozoic Era Continents crashing into each other create new mountain ranges like the Himalayas

109 109 Cenozoic Era Periodic ice ages create glaciers that reach into most of North America and other continents geography.howstuffw orks.com

110 110 Cenozoic Era Biological Changes Mammals evolve to replace the niches dinosaurs had occupied exurbanpedestrian.wordpress.com dearkitty.blogsome.c om

111 111 Cenozoic Era Biological Changes First grasses and flowering plants appear for the first time thoreaugrass.blogspot.com ruralramblings.com

112 Ice ages have caused mammals of the Cenozoic Era to adapt to many strange creatures. Cenozoic Era Biological Changes news.bbc.co.uk/2/hi/science/nature houseofstaunton.com/.../user-id=/password=

113 ESSENTIAL QUESTION #15 What types of catastrophic events have occurred over time? Comets and meteors have struck the planet causing global change. Many ice ages have occurred causing specie extinctions. Can you thing of others?

114 ESSENTIAL QUESTION #16 How did the geological theories of evolution assist Darwin in his theory of natural selection?

115 Change Over Time Charles Darwin At the age of 21, Darwin sailed on board the HMS Beagle as science officer richarddawkins.net Voyage of the HMS Beagle

116 Change Over Time Charles Darwin He studied the Galapagos Island wild life and noticed similarities between different species of finches, tortoises, and iguana photos.mongabay.com Notice the differences in the shells Notice the differences in the beaks Iguanas have evolved to eat cactus for one species and sea algae for another

117 Change Over Time Charles Darwin Based on these similarities, Darwin came to the conclusion that species evolved over time to adapt to different environments He called this adaptation natural selection or “survival of the fittest”

118 ESSENTIAL QUESTION #16 How did the geological theories of evolution assist Darwin in his theory of natural selection? He studied the different islands of the Galapagos He found that the islands had different climates and food sources therefore the animals had adapted to fit those environments. He also found that fossils in different parts of the world supported his theory.

119 ESSENTIAL QUESTION #17 How are the biological theories of Darwin and Lamark similar and how are they different?

120 Change Over Time Evolution Theory: an explanation that ties together many hypothesis and observations Adaptation: a trait that increases the chances that an organism will survive and reproduce Peppered Moth Can you see all four moths?

121 ESSENTIAL QUESTION ##18 How does the extinction of a species relate to evolution?

122 Change Over Time Evolution Natural Selection: survival of the fittest organisms that are the best adapted to their environment and the ones that will live long enough to reproduce and pass on their favorable adaptations

123 Lamark’s Views Jean-Baptiste Lamarck 1 August 1744 – 18 December 1829 Contributed his evolution theory before Darwin His theory included the idea that organisms developed traits because they needed them Example: A giraffe’s neck became longer because the giraffe would stretch it to reach food Although incorrect, his ideas began research into organisms changing over time.

124 ESSENTIAL QUESTION #17 How are the biological theories of Darwin and Lamark similar and how are they different? Both thought organisms had changed over time. Darwin supported natural selection. Lamark thought that organisms changed due to environmental stresses on them

125 Change Over Time Evolution Artificial Selection  the breeding of plants and animals with desired traits to attempt to produce offspring with these same traits  all domesticated animals and plants were developed using this process  also known as selective breeding

126 Change Over Time Evolution Speciation: the process of natural selection producing a new species out of existing species over thousands or millions of years Species: a group of organisms that can breed and produce fertile offspring; most specific classification of living things Extinction: The evolutionary termination of a species caused by the failure to reproduce and the death of all remaining members of the species; the natural failure to adapt to environmental change

127 Change Over Time Evolution Evolution: the change in population of a species over time; caused by differences in variation or successful mutations that allow individuals to survive and pass on their genes Mutation: a random change to a gene that results in a new trait Biological Evolution: the change over time of living organisms

128 ESSENTIAL QUESTION #18 How does the extinction of a species relate to evolution? If a species becomes extinct, they were not able to adapt to the changing environment. Only those able to adapt (change) will survive

129 129 Cenozoic Era Biological Changes First humans appear towards the end of the Cenozoic Era news.bbc.co.uk


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