Paleontology and Ecology Study Guide Questions & Answers Semester 1 Shiloh Middle School

1. What are fossils and how do they form? Fossils are preserved remains or traces of living things. Fossils form from decayed living matter (when living things die and are buried by sediments, which slowly harden into rock and preserve the shape of the organism.)

2. What type of rock usually contains fossils? Sedimentary rocks

3. What do paleontologists study? Fossils

4. Explain how the statement “History repeats itself” supports the principle of uniformitarianism“ This statement supports the principle of uniformitarianism because geological process (weathering, erosion, deposition, runoff-water cycle) that occurred in the past occur the same way today.

5. What is the law of superposition? In horizontal, sedimentary rock layers, the oldest layer is at the bottom and each layer higher is younger than the layers below.

6. Describe the condition of an organism that no longer exists on Earth. The organism is extinct.

7. How might fossils provide evidence of Earth’s past environment?  Fossils found in certain areas may tell whether the area was an ocean or a shallow sea.  Coral fossils found in Midwestern US tell that it used be an ocean long ago.

8.What is the geologic time scale? A record of the life forms and geologic events in Earth’s history.

9.Describe how life forms became more complex. There is evidence from fossils records that reveal major changes in life forms occurred at different times. Example: early bacteria shells insects fish dinosaurs mammals Simple to more complex

10.What do paleontologists use to help determine the age of rocks, according to the law of superposition? Relative age

11.What are index fossils? List an example of a very common index fossil.  Fossils of widely distributed organisms that lived during only one short period.  Trilobites

12.How do unconformities in rock layers form? Erosion wears away the surface of rock layers and then other rock layers form on top of the eroded surface.

13.What is the relative age of a rock compared to absolute age?  The relative age is the age compared to the ages of other rock or rock layers.  The absolute age is the number of years since the rock or rock layer formed. Relative Age Comparison Absolute Age EXACT

14.Where is the oldest layer of rock according to the law of superposition? The oldest rock layer is at the bottom.

15. Describe how sediments are deposited, according to the principle of horizontality. Sediments are deposited in horizontal layers, from left to right.

16. Justify how dinosaurs and horses did not exist during the same geologic era?  Fossils of dinosaurs or horses can NOT be found in the same rock layers.  Dinosaurs are EXTINCT!!

17. How do geologist determine the absolute age of rocks? Radioactive dating, after determining the rock’s rate of radioactive decay. Uranium – 238 has a half-life of 4.51 billion years and is used to date older rocks

18. Explain how a fossilized sea shell found at the top of a mountain supports Earth’s changing surface? The surface was once covered by water because a marine (water) environment would have been where the sea shell was.

19. A large elephant fossil found in a top layer compared to a small elephant fossil found below…what is the relative age? The rock layer that contains the large elephant fossil is YOUNGER. The rock layer with the small elephant fossil is OLDER. Top Layer Layer Below

20. What is the age of an intrusion in relation to the sedimentary rock layers it passes through? The intrusion is younger. YOUNGER…YOUNGER…..YOUNGER!!! G F /\/\/ E D IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII C IIIIIIIIIIIIIIIIIIIIIIIIIII B XXXXXXXXXXXXXXXXXXIIIIIIIIIIIIIIIIIIIIIIIIIIIIXXXXX A IIIIIIIIIIIIIIIIIIIIIIIIIIII

21. If a fossil of a palm leaf were found in Alaska, what would this suggest about Alaska’s climate? Alaska was once under warmer climates.

22. What are fossil fuels and how do they form? Fossils are preserved remains or traces of living things. Fossils form from decayed living matter (when living things die and are buried by sediments, which slowly harden into rock and preserve the shape of the organism.) Same question as #1

23. What is the disadvantage of nonrenewable resources? Nonrenewable resources take a long time to form and once they are used, they are gone. They will likely run out in the near future.

24. Give examples of renewable resources.  Biomass fuel  geothermal energy  hydroelectric power  solar energy  wind power

25. List some ways to conserve nonrenewable resources. Ride a bike, instead of driving cars to save gas. Insulate buildings to keep heat from being lost.

26. Hydroelectric power and wind energy are powered by what major energy source? What is (1) advantage to use this source of energy source? The sun, solar energy. It will not run out (in our lifetime)

27. Which of the following resources will run out in the near future? * fossil fuels (nonrenewable) X geothermal energy (renewable) X solar energy (renewable) X wind energy (renewable)

28. What are the three major fossil fuels? Coal, oil, and natural gas.

29. What is conservation? How does recycling help conserve energy resources? Conservation-To use our resources wisely Recycling does not require as much energy to be used.

30. Which of the following is the best alternative energy resource? geothermal energy (unlimited, only available in certain regions) oil (nonrenewable) natural gas (nonrenewable) hydroelectric power ( WATER)

31. How can a scientist determine where one period of geologic time ended and the next one began? The use of index fossils.