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. A scale model means that the timeline accurately depicts different lengths of time. All of the times that we are going to deal with in this lab are in millions 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 needed the 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 65 mya

End of Mesozoic 65 mya

Beginning of Mesozoic 248 mya

End of Paleozoic 248 mya

Beginning of Paleozoic 543 mya

End of Precambrian 543 mya Leave white unless you have time

Beginning of Precambrian (Formation of Earth) 4600 mya

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 Cenozoic5. 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 one Era, and beginning of another) Example: 0cm 8.5cm 32cm

7. VERY LIGHTLY COLOR each 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.

TODA

YEn

d of

Ceno

zoi

c

Begi

nCe

nozo

ic

End

ofM

esoz

oic

Begi

n M

esoz

oi

End

ofPa

leoz

oic

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 pages 668-669 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 248 mya

Permian 290 mya

Pennsylvanian 323 mya

Mississippian 354 mya

Devonian 417 mya

Silurian 443 mya

Ordovician 490 mya

Cambrian 543 mya

9. Next, get the Major Events handout from your teacher and determine which period each occurred. Refer to pages 668-669 in your text. Cut then paste each in the appropriate period on your timeline.

Questions1. What percent of the timeline falls in the Precambrian Era? (done for you)

[length of Precambrian era ÷ total age of Earth] 4057my ÷ 4600my (x 100) = 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) what percentage 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 reptilesTrilobites

Hominids develop.Modern horse, camel, elephant

develop.Giant dinosaurs. First birds.

Humans dominant. Domestic animals develop.

First amphibiansDinosaurs 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.