37 Mega Cities

Once again I am reminded of a common grade school science experiment I took part in as a child, the lesson of which has stayed with me my entire life.

Each student started with a glass jar with several ounces of fruit pectin and a well perforated lid. We added 6 to 10 fruit flies to each jar. The lid contained the fruit flies yet allowed for adequate air exchange. The amount of pectin was sufficient to sustain a growing population for a very long time. Over the course of a month or so each student was to count or estimate the population of flies in their jar and graph population growth. I remember the collective average of those graphs well.

After a month or so the population of every jar crashed and crashed fast, with all but a few reaching zero. That's when the real assignment started. Why did this happen when the flies had everything they needed for life? Why did the population not level off to a sustainable level? Why was the crash so consistent and repeatable? What could possibly be done to sustain the fly colony longer?

As engineers and scientists our contribution should be addressing those same questions for humanity, because the graph of human world population is looking all too familiar.