The Parable of the Bacteria in a Bottle

developed by Physics Professor Al Bartlett, U. Colorado

The Set-up

You place a single bacterium in a nutrient-filled bottle at 11:00 am. It grows and divides into two bacteria at 11:01. These two bacteria each grow and divide into 4 bacteria at 11:02, which grow and divide into 8 bacteria at 11:03, and so on. (i.e., doubling time of 1 minute.)

Bottle is full, nutrients gone, all the bacteria die.


  1. When was the bottle half-full?
  2. You are a mathematically-sophisticated bacterium, and at 11:56 you recognize the impending disaster. You immediately jump on your soapbox and warn that unless your fellow bacteria slow their growth dramatically, the end is just four minutes away. Will anyone believe you?
  3. Just before disaster strikes… a bacterial space program discovers three more bottles in the lab. With a population redistribution program, how much time do the 3 new bottles buy the colony?

Last Updated: 22nd June 2003