======Living or Not?======


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**Alternative titles:** Glue Monsters - Are They Alive? 
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====Summary====                   
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====Procedure====  
  - Place a Petri dish on an overhead projector.  
  - Fill it about halfway with tap water.  
  - Release a small drop of modeling glue onto the water’s surface (use a pipet to disguise the source).  
  - Prepare “food” by shaving wood and graphite from a pencil. Sprinkle near the glue droplet.  
  - Observe the glue “critter” as it moves, changes shape, and seems to eat the shavings.  
  - Add more glue droplets to observe how they interact.  
  - When the critters stop moving, discuss with students whether they showed characteristics of life.



====Links==== 
My Favourite Experiment - David Haller - Living or Not: 
{{youtube>T6mBkliJfIc?}}\\


📄 Glue Monsters—Are They Alive - Flinn Scientific: [[https://www.biologyjunction.com/images/misc/glue%20monsters.pdf]]\\

====Variations====
  * Use different colored backgrounds or lighting to enhance the visibility of movement.  
  * Have students list which characteristics of life the glue monster appears to display, and which it does not.



====Safety Precautions====  
  * Vapors are caustic - use in a well-ventilated area and avoid inhalation.



====Questions to Consider====
  * What characteristics of life did the glue monsters appear to show? (Movement, response to stimuli, feeding-like behavior.)  
  * What characteristics of life did they not show? (Growth, reproduction, cellular structure.)  
  * How does this activity challenge us to define what it means to be alive?  
  * Why is defining life sometimes considered a philosophical issue as well as a scientific one?