Changing Earth's Surface - Time After Time
Geologic time and human time are very different things. Earth is over 5 billion years old. Human life expectancy is about 76.1 years. To us, it takes forever to get to summer break at school. Learning to drive is in the far-off future. Who even thinks about marriage, careers and retirement? In geologic time, our lives last an instant. To demonstrate this you need a roll of toilet paper, some sticky notes, and a really long hall or straight sidewalk.
- Check with an adult first! Then unroll the entire roll down the hallway or sidewalk.
- If you have a roll with at least 400 squares, each square represents over 12 million years.
- Write "5 billion years ago - earth and other planets formed" on a sticky note and put it at the beginning of the roll.
- Count up the roll 104 squares. Write "Earths crust becomes solid," and place it on the square.
- Count up 16 more squares. You are now on square 120. Write "First life appears in oceans."
- Count up 20 squares. You are now on square 140. Write "Photosynthesis begins in oceans."
- Count up 108 squares. You are now on square 248. Write "First cells with nuclei in oceans - volcanic base deposit of Grand Canyon."
- Count up 100 squares. You are now on square 348. Write "First multi-cellular organisms appear."
- Count up 11 squares. You are now on square 359. Write "First land plants appear."
- Count up 21 squares. You are now on square 380. Write "Mass extinction of 99% of all life. Age of Dinosaurs begins."
- Count up 8 squares. You are now on square 388. Write "Supercontinent breaks up, continents drift apart."
- Count up 6 squares. You are now on square 394. Write "Age of Dinosaurs ends. Mass extinction of 70% of all living things."
- Count up 5 squares. You are now on square 399. Write "Colorado River begins cutting the Grand Canyon."
- Count up 1 square. Yes, you are on the last square. Write "First proto-humans appear in Africa."
- Measure 1 mm from the end. Write "First modern humans appear."
- If you can fit a note in put one .5 mm from the end. Write "Lake Bonneville exists."
- Measure .1 mm from the end. Write "Recorded history begins."
Wow. What a journey! You may want to make another timeline of the events of your life. You must remember that your entire timeline is less than one fiber of that last sheet of the Toilet Paper Roll of Geologic Time!