When you think of evolution what comes to

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When you think of evolution, what comes to mind? Draw a circle on your

When you think of evolution, what comes to mind? Draw a circle on your paper like the one below. Write down words, thoughts, or what you know (or think you know) about evolution. At the top write information related to geological evolution. At the bottom, write down information about biological evolution. Geological Evolution Biological

What is evolution? What are examples of evolution related to: 1. 2. 3. 4.

What is evolution? What are examples of evolution related to: 1. 2. 3. 4. 5. 6. Technology Earth’s Geology Living Things Environment Methodology Others ……. . Activity: “The Evolution of Technology”

Evolution: Theories & Evidence Gradual change over time: Biological evolution: - Charles Darwin’s “Theory

Evolution: Theories & Evidence Gradual change over time: Biological evolution: - Charles Darwin’s “Theory of Evolution” - natural selection; survival of the fittest; species/genetic variation - adaptations (adaptations box activity, Gizmo: Natural Selection, newspaper) Geological evolution: - Uniformitarianism - theory of plate tectonics, continental drift - Law of Superposition Environmental evolution: - ice cores (dissolved gasses), rock layers Life on Earth, as well as, the shape of Earth’s surface, has a history of change that is called evolution.

Theories of Evolution Charles Darwin (Biological Evolution) The 19 th century English scientist who

Theories of Evolution Charles Darwin (Biological Evolution) The 19 th century English scientist who carried out the necessary research to conclusively document that evolution has occurred and then made the idea acceptable for scientists and the general public. This man did not invent the idea of evolution. His work led to theory of natural selection and survival of the fittest. Lamarck (Chevalier de Lamarck) (Biological Evolution) Lamarck's explanation for evolution summarizes the idea that evolution occurs as a result of an organism acquiring a change in body shape due to using or not using particular body parts during its lifetime and then passing the new trait on to its offspring. Uniformitarianism (Geological Evolution) The theory that the gradual natural forces now changing the shape of the earth's surface have been operating in the past much the same way. In other words, the present is the key to understanding the past. From this view, the earth must be very old. What are some examples of “natural forces” that change earth’s surface?

Compare & Contrast Darwin’s Theory of Evolution Lamarck’s Theory of Evolution Theory of Uniformitarianism

Compare & Contrast Darwin’s Theory of Evolution Lamarck’s Theory of Evolution Theory of Uniformitarianism

Compare & Contrast Theories of: Charles Darwin’s Theory of Evolution Lamarck’s Theory of Evolution

Compare & Contrast Theories of: Charles Darwin’s Theory of Evolution Lamarck’s Theory of Evolution Theory of Uniformitarianism Charles Darwin’s Theory of Evolution - Research included investigations conducted of the Galapagos Islands Concluded that natural selection occurred by survival of the fittest Traits passed genetically from parent to offspring - Both Darwin’s theory and TOU are directly or indirectly related to environmental change - Both have evidence based on research Student Feedback: This is the data put together by students in classes 3– 6. Lamarck's Theory of Evolution Darwin & Lamarck - Related to theories of biological evolution - By either using or not using body parts in a certain way, new traits could be acquired Traits acquired after birth could be passed to offspring - All of these are “theories” - All involve the concept of “change over time” Theory of Uniformitarianism (TOU) - Related to only geological evolution - States that forces of nature (erosion, earthquakes, volcanoes, water, wind, etc. ) that changed the shape of earth in the past are continuing to do so Theory of Uniformitarianism

Evidence of Evolution of Organisms and Landforms * Comparative Anatomy *Species/Genetic Variations *Fossils *

Evidence of Evolution of Organisms and Landforms * Comparative Anatomy *Species/Genetic Variations *Fossils * The Fossil Record *Geologic Time Scale * Plate Tectonics * Continental Drift *Law of Superposition

Fossils as Evidence Fossils are the preserved remains or traces of once living things.

Fossils as Evidence Fossils are the preserved remains or traces of once living things. Fossils can be compared to one another and to living organisms according to their similarities and differences. 1. Mineral replacement/petrification: Minerals in water and soil replace the living material. (mold, cast) 2. Trace/Imprints: Imprints, footprints are left by the once living organism. 3. Carbonization: A thin layer of carbon is left by the once living organism. 4. Preservation of Actual Remains: (skin, bones, teeth, hair, etc. ) - amber - ice - tar (Le. Brea Tar Pits) - peat preservation Methods of Fossilization: Lab: “Fossil Identification” What can scientists learn by studying fossils? “Analyzing Trace Fossils” activity

The Relationship Between Sedimentation and Fossilization Sediments, sand smaller particles are gradually buried and

The Relationship Between Sedimentation and Fossilization Sediments, sand smaller particles are gradually buried and cemented together to form solid rock. More recently deposited rock layers are more likely to contain fossils resembling existing species. Thousands of layers of sedimentary rock not only provide evidence of the history of Earth itself, but also of changes in organisms. Rock Cycle 1. Why are fossils more likely to be found in sedimentary rock? 2. Why are fossils never found in igneous rock? 3. How can studying fossils in rock layers provide evidence of biological evolution? “Fossil Fun” What process may lead to the discovery of fossils? http: //www. abc. net. au/beasts/fossilfun/makingfossils/default. htm “Fossil Fun” online activity

3 2 1 Which rock layer do you think is the oldest, 1, 2

3 2 1 Which rock layer do you think is the oldest, 1, 2 or 3?

Igneous Intrusions cool inside Earth’s surface. Igneous Extrusions cool outside Earth’s surface. The Rock

Igneous Intrusions cool inside Earth’s surface. Igneous Extrusions cool outside Earth’s surface. The Rock Cycle Why are fossils more likely to be found in sedimentary rock?

Mineralization/Petrification: Minerals in water and soil replace the living material. Dinosaur skull Petrified wood

Mineralization/Petrification: Minerals in water and soil replace the living material. Dinosaur skull Petrified wood Trilobites and ammonites are used as “index fossils”. trilobite Index fossils ammonite

Trace or Imprint Fossils: Imprints, footprints are left by the once living organism 1

Trace or Imprint Fossils: Imprints, footprints are left by the once living organism 1 2 3 4 What can be inferred by studying each of these fossils?

“Traces of Tracks” Activity 1. What can you infer about picture #1? 2. What

“Traces of Tracks” Activity 1. What can you infer about picture #1? 2. What can you infer about picture #2?

Carbonization: A thin layer of carbon is left by the once living organism. Use

Carbonization: A thin layer of carbon is left by the once living organism. Use the concept of “comparative anatomy” to infer what each organism is. 1 1. 2. 2 What can be inferred by studying each of these fossils? How did you use the concept of “comparative anatomy” to reach your conclusions? 3 4

Actual Remains of Organisms Fossils Preserved in Ice 1 2 3 4 How does

Actual Remains of Organisms Fossils Preserved in Ice 1 2 3 4 How does ice allow for the preservation of actual remains?

Actual Remains of Organisms Fossils Preserved in Amber 3 a 1 2 3 4

Actual Remains of Organisms Fossils Preserved in Amber 3 a 1 2 3 4 3 b 1. 2. How does this method of preservation allow actual remains to be present? Based on “comparative anatomy” , what living organisms of today may they be descendants of?

Actual Remains of Organisms: Preserved in Tar The La Brea Tar Pits are a

Actual Remains of Organisms: Preserved in Tar The La Brea Tar Pits are a group of tar pits around which Hancock Park was formed, in urban Los Angeles. Asphaltum or tar (brea in Spanish) has seeped up from the ground in this area for tens of thousands of years. The tar is often covered with dust, leaves, or water. Over many centuries, the bones of animals that were trapped in the tar were preserved. 2 1 3 How did this method of preservation preserve the actual remains? http: //www. youtube. com/watch? v=G 7 FK 59 waeo 0 “La Brea Tar Pits: An Urban Mystery” 6: 08 min.

The Bog Bodies of Iron Age Europe http: //topractice. wikispaces. com/1+-+Arch. +of+Complex+Societies+Bog+bodies+term+paper (3: 51

The Bog Bodies of Iron Age Europe http: //topractice. wikispaces. com/1+-+Arch. +of+Complex+Societies+Bog+bodies+term+paper (3: 51 min. ) Bog bodies have been found in many locations in northwestern Europe: mostly in Ireland, England, Germany, and Denmark. Generally, these countries have poor preservation conditions, but the bogs are an exception to the rule. How did this method of preservation allow for the preservation of the actual remains?

http: //www. abc. net. au/beasts/fossilfun/ On-line Activity : “Fossil Fun” Burying Bodies Pitfall Skeleton

http: //www. abc. net. au/beasts/fossilfun/ On-line Activity : “Fossil Fun” Burying Bodies Pitfall Skeleton Jigsaws Making Fossils Color and Camouflage Footprints Game

Carbon-14 dating is a way of determining the absolute age of certain objects of

Carbon-14 dating is a way of determining the absolute age of certain objects of a biological origin(actual remains) up to about 50, 000 years old. It is used in dating things such as bone, cloth, wood, skin and plant fibers. This will be discussed when we

Based on what scientists have learned from the fossil record, they have developed the

Based on what scientists have learned from the fossil record, they have developed the Eons Eras Periods Epochs Largest……. ……………. To…………. Smallest

Geologic Time Scale http: //www. youtube. com/watch? v=7 PQURsc 2 SYs “Geologic Timeline Music

Geologic Time Scale http: //www. youtube. com/watch? v=7 PQURsc 2 SYs “Geologic Timeline Music Video” 4: 23 1. Which time periods are the longest? 2. Which time periods are the shortest Mass Extinction: Meteor hits Earth leads to environmental change Mass Extinction: Continental drift leads to environmental change Precambrian Eon bacteria: single-celled organisms Coach Lesson 29

Eons are not shown. Cont. Geologic Time Scale Compare to an annual calendar. http:

Eons are not shown. Cont. Geologic Time Scale Compare to an annual calendar. http: //www. esse. ou. edu/fund_concepts/Fundamental_Concepts 4/Geologic_Time_Scale. html

Using the Geologic Time Scale, answer the questions. 1. Which included the longest amount

Using the Geologic Time Scale, answer the questions. 1. Which included the longest amount of time: eons, eras, periods, epochs? 2. In which era are we living? 3. In which period are we living? 4. Which organism evolved first, the first land plants or the first reptiles? 5. Put the following organisms in order from oldest to youngest. first amphibians, first birds, first flowering plants, first mammals 6. Scientists believe that Earth is approximately how old? You may use the Geologic Time Scale at your table to answer the questions. Distribute student copies. *Anatomical similarities and differences between organisms living today and between them and organisms in the fossil record enable the reconstruction of evolutionary history and inference of lines of evolutionary descent.

Eon

Eon

Extinction of Species 1. Most species that have lived on the earth are now

Extinction of Species 1. Most species that have lived on the earth are now extinct (99%). 2. Extinction occurs when the environment changes and organisms do not have traits necessary to survive and reproduce. 3. Some organisms that lived long ago are similar to existing organisms, but some are quite different. 4. Extinction of species is apparent in the fossil record. 5. Mass extinctions occurred at the end of each era. 6. Scientists believe that 99% of all organisms that ever lived on Earth have become extinct.

Environmental Changes: Natural process and human activities result in environmental changes. • Natural Processes:

Environmental Changes: Natural process and human activities result in environmental changes. • Natural Processes: – – • Human Factors: Earthquakes Movements of ice sheets Volcanoes Plate Tectonics/Continental Drift – Pollution: decrease in air and water quality. – Deforestation: increased erosion because of decrease in tree population. – Global Warming: increased temperature leads to melting of ice caps and changes in sea levels. • Will lead to changes in sea level, changes of height in land, and changes in climate.

The Fossil Record The collection of fossils and their placement in chronological order (through

The Fossil Record The collection of fossils and their placement in chronological order (through location of sedimentary layers in which they are found or through radioactive dating) is known as the “fossil record”. What have scientists learned by studying the fossil record? • Existence of organisms • Diversity of organisms • Relationship between organisms • Time of mass extinctions • Evolution of organisms • Adaptations of organisms • Climate changes • Links to geological evolution Student Geologic Timeline Project

Geological Evolution: Find the link. http: //www. youtube. com/watch? v=Yg. E-d. Sx-f. Pc “Grand

Geological Evolution: Find the link. http: //www. youtube. com/watch? v=Yg. E-d. Sx-f. Pc “Grand Canyon Superposition” 5: 51 min

Law of Superposition In undisturbed rock layers, the oldest rock layers are on the

Law of Superposition In undisturbed rock layers, the oldest rock layers are on the bottom and the youngest layers are on the top. An “unconformity” is a disruption in a rock layer. This may be caused by geologic forces or erosion from wind, water, etc. .

The Law of Superposition “Who Dun it? ” Activity http: //www. jbole. com/worksheets/Who. Dunit.

The Law of Superposition “Who Dun it? ” Activity http: //www. jbole. com/worksheets/Who. Dunit. pdf Someone took the last cookie in the cookies jar last night. The last person to leave the scene is the culprit. Who was it? Someone took the last cookie in the cookie jar last night. The last person to leave the scene is the culprit. Who was it? Clues: The Butler walks to work. The Handyman rides a bike. The Cook rides a motorcycle. The Maid drives a car. The Nephew has a seeing-eye dog. Use the clues to solve the mystery. Good luck. 1. Who took the last cookie? 2. Explain your reasoning using the concept of the Law of Superposition. 3. Put the people in order from 1 to 5 with 1 being who arrived at the scene first and 5 as who arrived last.

Unconformities 1. What is evidence of an unconformity? 2. What may have caused the

Unconformities 1. What is evidence of an unconformity? 2. What may have caused the unconformity? 3. What is evidence of sedimentation? 4. In “Time 2” what is the oldest layer? 5. In “Time 3” what is the oldest layer? 6. In “Time 4” what is the oldest layer? The red layer is an example of a ______.

SG: “The Relative Age of Rocks” 1. Which rock layer is the oldest? Explain.

SG: “The Relative Age of Rocks” 1. Which rock layer is the oldest? Explain. 2. Which rock layer is the youngest? Explain. 3. Does this tell the absolute or relative age? Explain. Even through “folding” has occurred, the layers are in their original order. 4. In which type of rock can absolute age be determined?

Intrusions • Areas in Earth’s crust where magma has cooled before it reached the

Intrusions • Areas in Earth’s crust where magma has cooled before it reached the surface forming an igneous intrusion • Intrusions are always younger than the rock layers they go through. Igneous intrusion 1 5 2 3 4 “Finding Clues to Rock Layers” Put the layers in order from oldest to youngest.

1 2 3 4 6 1. Which layer is the igneous intrusion? Explain. 2.

1 2 3 4 6 1. Which layer is the igneous intrusion? Explain. 2. Put layers 1 – 6 in order from oldest to youngest. 5

1. How old are layers 3 and 4? (Provide quantitative data. ) 2. Layer

1. How old are layers 3 and 4? (Provide quantitative data. ) 2. Layer 2 is _________ than layer 1. 3. Layer 3 is _________ than layer 4. Does this provide “absolute” or 4. Layer 1 is _________ than layer 2. “relative” age? Explain.

http: //www. youtube. com/watch? v=Xs 4 y. NL 1 M 8 Gg “How The

http: //www. youtube. com/watch? v=Xs 4 y. NL 1 M 8 Gg “How The Earth Was Made: Ring of Fire” 43: 37 min. Fault lines are the breaks in Earth’s crust where tectonic plate boundaries exist.

Plate Tectonics • The movement of Earth’s continental (land) and oceanic (ocean) plates has

Plate Tectonics • The movement of Earth’s continental (land) and oceanic (ocean) plates has caused mountains and deep ocean trenches to form and continually change the shape of Earth’s crust. • These movements have caused plates to pass through different climatic zones. This movement of the continents is called “continental drift”. Activity: “Modeling Seafloor Spreading” http: //www. pbslearningmedia. org/resource/ess 05. sci. ess. earthsys. plateintro/pla te-tectonics-an-introduction/ plate tectonics 2: 22 min.

Evidence of Continental Drift/Seafloor Spreading 1. Coastline similarities 2. Fossil similarities 3. Glaciers (movement,

Evidence of Continental Drift/Seafloor Spreading 1. Coastline similarities 2. Fossil similarities 3. Glaciers (movement, concentration of dissolved gasses and other substances) 4. Age and types of rocks 5. Rock magnetism

Hotter magma is less dense so it rises. Magma cools as it rises making

Hotter magma is less dense so it rises. Magma cools as it rises making it more dense. As the density increases, the magma begins to sink. As the magma moves, so does the plate that is above it. http: //www. youtube. com/watch? v=Kpoko_l 34 ZE Convection Currents 1: 06 Activity: “Convection Currents” Convection Currents Green represents continental plates. Diverging Plates Converging Plates Magma cools as it rises to the surface. It becomes more dense and will sink. Magma near the core is hotter and less dense; therefore, it will rise.

Mid Ocean Ridges http: //www. youtube. com/watch? v=b. Gye 6 vl. Opb. Y “The

Mid Ocean Ridges http: //www. youtube. com/watch? v=b. Gye 6 vl. Opb. Y “The Mid-Atlantic Ridge” 2: 53 Activity: “Modeling Seafloor Spreading” At which location are the rock layers older, A, B or C? Explain. C B A rift valley A B C

Why does this diagram show a convergent plate boundary and not a divergent plate

Why does this diagram show a convergent plate boundary and not a divergent plate boundary? “Modeling Convergent Plate Movement” activity Subduction zone

Where is a divergent plate boundary shown? Where is a convergent plate boundary shown?

Where is a divergent plate boundary shown? Where is a convergent plate boundary shown?

Ice Cores: Evidence of Environmental Evolution http: //www. pbs. org/wgbh/nova/warnings/stories/ Record these 8 examples

Ice Cores: Evidence of Environmental Evolution http: //www. pbs. org/wgbh/nova/warnings/stories/ Record these 8 examples in your notebook. (Dissolved gasses) Scientists collect ice cores by driving a hollow tube deep into the miles-thick ice sheets of Antarctica and Greenland (and in glaciers elsewhere). The long cylinders of ancient ice that they retrieve provide a detailed record of what was happening in the world over the past several ice ages. That's because each layer of ice in a core corresponds to a single year—or sometimes even a single season—and most everything that fell in the snow that year remains behind, including wind-blown dust, ash, atmospheric gases, even radioactivity.

What is the relationship between CO 2 and temperature?

What is the relationship between CO 2 and temperature?

Ice Cores Provide Evidence of Radioactivity 1986 - Radioactivity In April 1986, Russia's nuclear

Ice Cores Provide Evidence of Radioactivity 1986 - Radioactivity In April 1986, Russia's nuclear power station at Chernobyl exploded, killing 250 people and sending radioactive fallout around the world. Less than two years later, as the graph indicates, scientists detected Chernobyl radioactivity in snow at the South Pole. In cores from Antarctica and Greenland, researchers have pinpointed the beginning of atomic-bomb testing in the mid-1950 s. They have also identified a spike representing fallout from stepped-up atmospheric testing that took place just prior to the 1963 Test Ban Treaty, which allowed for underground tests only. In the years following 1965, by which time some 90 countries had signed the treaty, Antarctic snow revealed a sharp drop in radioactive fallout.

Ice Cores Provide Evidence of Air Pollution 1900 - Air Pollution Gases trapped in

Ice Cores Provide Evidence of Air Pollution 1900 - Air Pollution Gases trapped in ice cores show the dramatic impact that human activities have had on the planet since the Industrial Revolution. The first graph reveals how atmospheric carbon dioxide, methane, and nitrous oxides from coal and oil burning power plants, cars, and other fossil-fuels (coal, oil, natural gas) The burning of fossil fuels has climbed along with the world population, with as yet unknown effects on the climate system.

Ice Cores Provide Evidence of Sea Storminess 1400 AD - Sea Storminess Viking colonies

Ice Cores Provide Evidence of Sea Storminess 1400 AD - Sea Storminess Viking colonies in Greenland abruptly vanished toward the end of the 14 th century. This graph, which combines results from cores taken in both Antarctica and Greenland, tracks sodium levels over the past 1, 200 years. In colder periods, seas become stormier because of the greater contrast in temperatures between the tropics and the poles, and so more sodium—an indicator of sea salt—winds up on the ice caps. About 1400 AD, the cores at both poles clearly show a sharp rise in sodium, which some scientists say marks the onset of the Little Ice Age, a period of much cooler temperatures that lasted into the 19 th century. For the Vikings, a series of abnormally cold winters in the late 1300 s spelled doom.

Ice Core Evidence of Pollution 1167 AD – Dating Annual layers of snowfall in

Ice Core Evidence of Pollution 1167 AD – Dating Annual layers of snowfall in ice cores can be counted as easily as tree rings, allowing precise dating of events such as volcanic eruptions. Distinct annual layers stand out because, in snow that falls in summer, crystals are larger and acidity higher than in winter snow. In some cases, scientists can even tell seasons apart, by using a laser to measure the concentration of dust particles. (Winds are generally stronger in springtime, meaning more dust gets blown into the atmosphere. ) In this photograph of an ice core drilled in the Kunlun Mountains of western China, the thick, lighter bands indicate heavy snowfall during the monsoon season in the year 1167 AD, while thinner, darker strips show layers of dust blown into the snowfield during the dry season.

Ice Core Evidence of Climate Change 12, 000 BP (before present) - Rapid Climate

Ice Core Evidence of Climate Change 12, 000 BP (before present) - Rapid Climate Change As this graph shows, a jump occurred about 12, 000 years ago, as the last glacial period (the Pleistocene) was giving way to our current warm "interglacial" period (the Holocene). Suddenly, possibly in less than five years, average temperatures, which were slightly cooler than today's, plunged by about 27°F, returning the world to near-glacial conditions. As the graph indicates, calcium levels tend to go up and snow accumulation down with temperature. The Younger Dryas, as this freak period is known, lasted about 1, 300 years before it returned—just Ice cores have revealed that global climate—long thought to change only very as abruptly—to the temperatures typical of the gradually—can shift with frightening speed, period immediately preceding it. in some cases in a matter of years.

Ice Core Evidence of Temperature Change Background information on isotopes not necessary to learn

Ice Core Evidence of Temperature Change Background information on isotopes not necessary to learn as part of the standards. (Optional) • Temperature has yo-yoed over the ages as wildly as it does through any single year. Like natural thermometers, ice cores have recorded these fluctuations, which scientists can "read" by examining *isotopes of oxygen and hydrogen in water trapped in the ice. The data in this graph, gleaned from a core drilled in central Greenland, shows how temperatures have risen by more than 20°C (36°F) since the height of the Ice Age 25, 000 years ago. • Isotope: each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element.

Ice Core Evidence of Volcanic Activity 73, 000 BP - Volcanic Eruptions Approximately 73,

Ice Core Evidence of Volcanic Activity 73, 000 BP - Volcanic Eruptions Approximately 73, 000 years ago, an Indonesian volcano known as Toba erupted with enough force to send more than 600 cubic miles of volcanic material into the atmosphere. Such violent, so-called caldera eruptions can drastically alter global climate, by spewing so much ash and sulfur compounds into the atmosphere as to block sunlight and lower temperatures worldwide. Detected on this graph, which displays volcanic sulfate levels between 20, 000 and 110, 000 years ago, Toba was the largest eruption of the past 500, 000 years. (The seemingly larger spike at about 53, 000 years ago involved a series of smaller eruptions on Iceland, which is far closer than Toba is to Greenland, where this core was taken. ) Ice cores offer scientists the best means available to learn how past eruptions have affected climate—and thus to predict the impact that future ones might have. If an eruption on the order of Toba, which climatologists believe may have led to as much as several centuries of cold climatic conditions, were to occur today, it could seriously disrupt life on Earth. (Yellowstone Nat. Park caldera)

Ice Core Evidence of Global Warming 160, 000 BP - Global Warming Many scientists

Ice Core Evidence of Global Warming 160, 000 BP - Global Warming Many scientists fear that rising levels of socalled "greenhouse gases" from the burning of fossil fuels (coal, oil and natural gas) and other human activities will cause global warming, with potentially grave consequences for human agriculture and society. One of the clearest signs that elevated levels of greenhouse gases can result in warming comes from an ice core taken near the Russian Vostok station in Antarctica. At about 360 parts per million, the amount of CO 2 in the atmosphere today far exceeds levels at any time in the past 160, 000 years—indeed, This graph tracks temperature and atmospheric levels in the past few million years. For those worried of carbon dioxide (CO 2) and methane (CH 4) from the about global warming, this is a sobering present back to about 160, 000 years ago. (This represents about 11, 350 feet of ice accumulation. ) The statistic. graph clearly shows how a rise in gases will mean a rise in global temperature (though whether rising gases trigger rising temperatures, or vice versa, remains unknown). Also note that (though the graph, which has data up to two decades old, does not show this), What are possible consequences of global warming? http: //video. nationalgeographic. com/video/101 -videos/ global-warming-101 “Global Warming : 101“ 3: 04

Determining Relative and Absolute Age Relative Age: the age of a rock or fossil

Determining Relative and Absolute Age Relative Age: the age of a rock or fossil described in comparison to that of another rock or fossil. • Methods: • Law of Superposition • Use of index fossils Absolute Age: the actual age of a rock or fossil (actual remains), or how long age it formed • Methods : • Radiometric/Radioactive Dating with igneous rock • Radiometric/Radiocarbon Dating (with actual remains)

Radioactive Decay Henri Becquerel Marie and Pierre Curie • Most elements are stable: If

Radioactive Decay Henri Becquerel Marie and Pierre Curie • Most elements are stable: If they are not part of a chemical reaction, they do not change. • Chemical elements are made of atoms. In stable elements, the atom stays the same. • In the 19 th century, Henri Becquerel discovered that some chemical elements have atoms that change. During their change they send out a particle. In 1898, Marie and Pierre Curie called this phenomenon radioactive decay. • The time it takes, on average for half the atoms of a substance to change/decay is called half-life.

Radioactive/Radiometric Dating: a means of measuring the absolute age of a material by comparing

Radioactive/Radiometric Dating: a means of measuring the absolute age of a material by comparing the amount of a radioactive (unstable) form of an element with the amount of its decay (stable) element Radioactive Decay: the spontaneous break down of a radioactive substance along with the emission of radiation

Radioactive Elements List http: //periodictable. com/Elements/Radioactive/ Radioactive Elements and Half-lives http: //www. buzzle. com/articles/list-of-radioactive-elements.

Radioactive Elements List http: //periodictable. com/Elements/Radioactive/ Radioactive Elements and Half-lives http: //www. buzzle. com/articles/list-of-radioactive-elements. html

Radioactive (unstable) Elements & Decay (stable) Elements 1. By what percent does the radioactive

Radioactive (unstable) Elements & Decay (stable) Elements 1. By what percent does the radioactive element decrease after each half life? Radioactive Element (g) 2. What is the relationship between the radioactive (unstable) element and the decay (stable) element? 1 st Half life 2 nd Half life 3 rd Half life 4 th Half life

 Half-life Mass of Original Carbon-14 Remaining (g) Mass Of Decay Element Nitrogen-14 Number

Half-life Mass of Original Carbon-14 Remaining (g) Mass Of Decay Element Nitrogen-14 Number of Years Carbon 14 is used to determine absolute age of actual remains. 0 100% 0 0 1 50% 5, 730 2 25% 75% 11, 460 3 12. 5% 87. 5% 17, 190 4 1. 2. 3. 4. 5. 6. Complete the data for the 4 th half-life. What is the “stable” element in the above data table? Explain. What is the “unstable” element in the above data table? Explain. What is the half-life of carbon-14? Explain. By what percent does carbon-14 decrease after each half-life? By what percent does nitrogen-14 increase after each half-life? How many half-lives must pass before 25% of the carbon-14 is remaining?

Radiocarbon Dating Charcoal, wood, twigs and seeds bone Marine, estuarine and riverine shell. Leather

Radiocarbon Dating Charcoal, wood, twigs and seeds bone Marine, estuarine and riverine shell. Leather Peat Coprolites (samples of preserved feces). Lake muds and sediments. Soil Ice cores Pollen Hair Pottery Metal casting ores Wall paintings and rock art works Iron and meteorites Bird eggshell Corals and foraminifera Blood residues Textiles and fabrics Paper and parchment Fish remains Insect remains Resins and glues Antler and horn Water Carbon 14 = radioactive (unstable) element Nitrogen 14 = decay (stable) element Half-life: the time it takes for half of a radioactive element to decay What is the “half-life” of carbon 14? As the radioactive element _____, the decay element will ______.

Half-Life: the amount of time it takes for a radioactive element to decay into

Half-Life: the amount of time it takes for a radioactive element to decay into its “decay element” Major Radioactive Elements Used in Radiometric Dating Radioactive Element Decay Element “Absolute age” can only be determined with materials that have the radioactive element in them. Half-Life of Radioactive Element Effective Dating Range (Years) Minerals and Other Materials that can Be Dated

1. How can you tell that the “stable decay element” and the “radioactive material

1. How can you tell that the “stable decay element” and the “radioactive material X“ are correctly labeled? 2. What is the “half-life” of the radioactive (stable) element? 3. How many half-lives will occur before half of the decay element is present? Twizzler Activity: “Modeling Radioactive Decay” Practice: “Decay of Radioactive Material” SG: “Radioactive Dating of Rocks” Time ( X 10, 000 years)