Activities

1. Define the Law of Superposition.
   
   
2. Fossils are:
   1. The remains of organism that were killed by a meteor over 20,000 years ago
   2. Direct evidence of organisms that lived more than 10,000 years ago
   3. Proof of evolution
   4. Impressions of dinosaur bones in igneous rocks
      
      
3. The body of an organism is more likely to become fossilized if it:
   1. Dies in the ocean
   2. Is buried deeply in the ground
   3. Is buried on top of the ground
   4. Does not contain bones or other hard body parts

4. You are going fossil hunting in Pennsylvania’s coal region. Do you think you will find more animal fossils or more plant fossils in that area? Explain your answer.

5. It is common knowledge that a paleontologists’ interpretation of the fossil record has been biased. Explain how this bias might influence our current knowledge about the plants and animals once lived throughout Pennsylvania’s history.

Answer Key/Rubric

1. The Law of Superposition states that older rocks are found deeper in the earth’s crust than younger rocks.
   
   
2. B
   
   
3. B
   
   
4. Acceptable responses might include, but not be limited to:
   More plant fossils will be found because coal is a thick accumulation of plant material that is pressurized and buried deeper into the ground.

5. Acceptable responses might include, but not be limited to:
   The fossil record is not complete. Some species are either underrepresented or have not yet been discovered therefore scientists have an incomplete picture of the past. What scientists know about Pennsylvania’s history could change with the discovery of an older (or younger) plant or animal fossil that realigns the current fossil record. Also, improved technology could increases the accuracy of carbon dating and alter the fossil record.