Earth History and Fossils

Earth's History & Fossils

8th Grade Science

Spring 2021

Multiple Choice

What are reasons for gaps in the fossil record?

• Many organisms do not have structures that can be fossilized. (There bodies are made of soft tissues instead of shells or bones)

• Some environments do not provide conditions favorable to fossil formation. (If the environment is not made from sedimentary rock we will not have fossils.)

• There are lots of fossils that we haven't found yet. (Because you need to either dig or look in mountains we are still searching for many fossils/ index fossils to help us fill the gaps of the fossil record.)

• Some geological events destroyed fossils that were in the rock layers. (Things like earthquakes and volcanic eruptions may have destroyed important fossils).

• All of the above.

Multiple Choice

Subdivision of a period; shortest division of geologic time. 

• Eon 
• Era 
• Period 
• Epoch 

Multiple Choice

Subdivision of an Era

• Era 
• Eon 
• Period 
• Epock

Multiple Choice

Subdivision of an eon (Paleozoic, Mesozoic, Cenozoic)

• Era 
• Period
• Epoch 
• Eon 

Multiple Choice

Very large division of geologic time; usually referred to as the longest division of time. 

• Era
• Epoch 
• Eon 
• Period

Multiple Choice

The system of time measurement involving the formation of and changes of the Earth. 

• Index Fossil 
• Geologic Time Scale 
• Law of Superposition 
• Preserved Fossil 

Multiple Choice

The age of the Earth is measured in _______ of years.

• millions

• billions

What's your period?

Complete the Geologic Timeline Research Project on Canvas:

https://glcsd.instructure.com/courses/2073/assignments/95447