I recently saw an interesting mathamatical simulation used by a UN worker to
explain the multi-variable nature of helping a small village to high students.
Say you start with a community of 500 where the infant death rate is 80%,
available water is fixed and just enough to serve the community, and food
comes from farming -- and they aren't using modern methods.
Pretty much anything you do to help these people will increase population and
pretty much nothing you can do will increase water. In a few years the small
town that you tried to help will be suffering from water shortages. Because
water is getting used to drink, water won't be available for farming, so the
increased population will also lead to famine. Death returns with a new face.
The only solution is to teach people they don't need to have 10 children to
garruntee that two will make it to adulthood. If people learn from experience,
this lesson will take one generation to learn - but that is too long a
timescale for this.
Has anyone seen (or done) a calculation of energy needs that takes into
account both population growth as well as deaths due to AIDs?