======Geological Timeline with Toilet Paper ======


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**Alternative titles:** The Toilet Roll of Time
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====Summary====                   
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====Procedure====  
  - Count out 46 sheets of toilet paper. Each sheet represents 100 million years.  
  - Number each sheet from 0 to 45 with a marker.  
  - On the final sheet, mark the age of Earth (4.567 billion years ago). Fold under or cut off extra paper.  
  - Cut out timeline markers for major events (e.g., origin of life, early plants, dinosaurs, humans).  
  - Lay out the toilet roll in a long strip on the floor.  
  - Place the timeline markers in the correct positions along the strip.  
  - Glue or staple the markers to the paper.  
  - Review the distribution of events and notice that nearly all significant events are concentrated in the last 600 million years.


====Links==== 
Video lab: Paper Geologic Timeline - ScienceGonnaGetYou: 
{{youtube>mq4YStqyQqk?}}\\

📄 The toilet roll of time - Earthlearningidea: [[https://www.earthlearningidea.com/PDF/234_Toilet_roll_of_time.pdf]]\\

====Variations====
  * Use a longer roll to increase resolution (e.g., 1 sheet = 10 million years).  
  * Create a wall display version instead of a floor layout.  
  * Add additional events, such as the rise of humans, Ice Ages, or major volcanic eruptions.  
  * Compare geological time with a 24-hour day to emphasize scale.



====Safety Precautions====
  * Use scissors carefully when cutting the roll or markers.  
  * Ensure enough space so the roll does not become a tripping hazard.




====Questions to Consider====
  * Why do most of the important evolutionary events occur in only the last few sheets of the roll? (Complex life evolved relatively late in Earth’s history.)  
  * How long did bacteria dominate Earth before multicellular organisms appeared? (About 1.5 billion years.)  
  * What does this model teach us about the scale of human history compared to Earth’s history? (Humans appear only in the last fraction of a sheet, showing our very recent arrival.)  
  * How does this activity help us better understand geological time? (It makes the abstract concept of billions of years tangible and easier to visualize.)