Earth History Timeline Name/Date/Block: ______
Purpose: To create a model of the entire history of the Earth.
Introduction: We are going to make a scale model of Earth’s history. Ascale model means that the timeline accurately depicts different lengths oftime. All of the times that we are going to deal with in this lab are inmillions of years ago (mya).
Procedure:
1. Our first step will be to place the four Eras on the timeline. Use the equation below to determine the length each will be placed on the timeline.
To figure out the equation for the lengths neededthe following proportion was used:
Length on Timeline age of event (mya)
Length of whole timeline = age of earth (mya) 4600 mya = 600cm so…
Equation: Length on Timeline = ([age of event] ÷ 4600mya) x 600cm
Name of Era / Age of Event / Length on Timeline (cm) / Color(Today)End of Cenozoic / 0 mya
Beginning of Cenozoic / 65mya
End of Mesozoic / 65mya
Beginning of Mesozoic / 248mya
End of Paleozoic / 248mya
Beginning of Paleozoic / 543 mya
End of Precambrian / 543mya / Leave white unless you have time
Beginning of Precambrian (Formation of Earth) / 4600mya
2. You will need 6m of ticker tape paper.Tape it to the ground/desk so that it is all of the way open.
3. Label (in small letters) one end Formation of Earth / Beginning of Precambrian
4. Label the other end Today / End of Cenozoic
5. All of our times are in millions of years ago, so MAKE EVERY MEASUREMENT from the end that says TODAY.
6. Label the events (HINT: Use one line, and label one side end of oneEra, and beginning of another)
Example:
0cm 8.5cm 32cm
7. VERY LIGHTLY COLOReach era, you will need to write there later so don’t make it too dark. Leave the Precambrian white for now. If you have time go back and color it.
8. Each Era is broken up into Periods. Using the same equation as before, you need to label each of the following Periods.Refer to pages668-669 in your text.
Name of Period / Age each begins / Length on Timeline (cm)Quaternary / 2 mya
Neogene / 24 mya
Paleogene / 65 mya
Cretaceous / 144 mya
Jurassic / 206 mya
Triassic / 248mya
Permian / 290mya
Pennsylvanian / 323mya
Mississippian / 354mya
Devonian / 417mya
Silurian / 443mya
Ordovician / 490mya
Cambrian / 543mya
9. Next,get theMajor Eventshandout from your teacher and determine which period each occurred. Refer to pages668-669 in your text. Cut then paste each in the appropriate period on your timeline.
Questions
1. What percent of the timeline falls in the Precambrian Era?(done for you)
[length of Precambrian era ÷ totalage of Earth] 4057my÷4600my(x100)= 88%
2. What percent of the Earth’s history have humans been in existence?
3. What percent of the Earth’s history has there been abundant fossils?
4. The universe is about 15 billion years old (15000 million) whatpercentage of that time has the Earth been in existence?
Major Events: Determine which period each occurred using your text as a reference. Cut out and paste each in the appropriate period on your timeline. Find a way to make them fit!
Stromatolites, simple marine organisms. No life. /
First reptiles /
Trilobites
Hominids develop.
Modern horse, camel, elephant develop. /
Giant dinosaurs. First birds. /
Humans dominant. Domestic animals develop.
First amphibians /
Dinosaurs die out. /
Graptolites
Crinoids /
Mass extinction. Final uplift of Appalachians. /
First land plants
Reptiles thrive. Forests of conifers and cycads. /
Many new mammals appear. Pygmy horse. First whales.