Shuck and Jive

Monday, December 15, 2008

Zero Population Growth Will Happen

this next installment, Dr. Bartlett continues with examples of the exponential function. He talks about world population.

On July 7, 1986, the news reports indicated that the world population had reached 5 billion people growing at a rate of 1.7% per year.
That doesn't sound like much. You calculate the doubling time 70/1.7% = 41 years.
In 1999, the world population had reached 6 billion, but growing at 1.3% per year. Doubling time = 53 years. However, Earth adds 80 million new humans every year.
Dr. Bartlett extrapolates this modest 1.3% per year growth to the future.
If this modest 1.3% per year could continue, the world population would reach a density of one person per square meter on the dry-land surface of the earth in 780 years. And the mass of people would equal the mass of the earth in just 2400 years.
Dr. Bartlett points out that we smile at that. We know that won't happen. Why? Because, eventually zero population growth is going to happen. We can debate whether or not we like it. Regardless, it will happen. Today's high birth rates will drop and low death rates will rise far sooner than 780 years.

Then he asks, "What sort of options are available if we want to address the problem?" He offered this

Table of Options

Increase Populations Decrease Populations






Large Families

Small Families





Public Health





Law and Order



Scientific Agriculture


Accident Prevention


Clean Air

Pollution (smoking)

Ignorance of the Problem

The items on the left are the good things we do that lower the death rate. But anything we do that lowers the death rate makes the problem worse. The things on the right are those things that are going to solve the problem. We have a dilemma. Those things on the left we regard as good and sacred. Those things on the right (murder, war, famine, disease) we do not want.

Now, the point. We eventually are going to reach zero population growth. Nature will choose from those items on the right. Dr. Bartlett says:

We don't have to do anything except be prepared to live with whatever nature chooses from that right hand list. Or we can exercise the one option that is open to us: choose something from the right hand list that we can go out and campaign for.
Nature is already choosing. AIDS is one example. Famine and war are others. He asks an interesting question: where is education on this table? Is it on the right hand column or left? He thinks that so far, it is on the left. Education has not addressed this problem.

He doesn't mention religion, but I'll let you be the judge.

It appears to me that the best item on the right would involve decreasing birth rates. It seems that we ought to be campaigning for contraception and family planning and reorient our values so that every child born is a wanted child.

Or we can let nature take its course. And it will.


  1. In the past people had lots of babies because lots of babies died. The problem is that it takes a while for people to adjust their behaviour patterns to new situations. Of course, in the affluent west population growth has slowed down and is, in some places, reversing. There is good evidence that in some developing countries, such as India, a slowing down in growth has already started.

    Therefore, the best thing we can do to stop population growth is to make the whole world healthy and comfortably above absolute poverty. If done today this would result in zero population growth before 2050.

  2. I trust mother nature to fix the problem.

  3. In many parts of the world, Europe, China and Japan, the birthrate has dropped below replacement levels.

    This brings on certain problems, though. The average age of the population increases. Elderly people can't work and rely on younger workers to support them. With increasing life expectancies, the problem becomes more acute.

    We need younger people to provide for social security for older people.

    So, a better solution for the population problem is to increase the death rate so that the median age is about twenty five.

    We should eliminate flu shots for the elderly and encourage smoking and fast food diets.

  4. Hey Madpriest,

    The United States is certainly affluent. We should be as we make up 5% of the world's population and consume 25% of the world's oil. Yet the population of the United States is increasing. We do not have zero population growth.

    We may as a planet reach zero population growth by 2050, but I don't think it will be because we have moved out of poverty. It will be because we have exceeded the ability of the planet to sustain our population.

    We also think of overpopulation as a problem for the underdeveloped countries. Yet, in terms of per capita consumption of resources, those in affluent countries make much higher demands on our natural resources per person.

    Bartlett says the U.S. should take the lead by example in terms of zero population growth today. I tend to agree.

  5. Jodie,

    You put your money on a sure bet. Nature will take care of the problem. I question the ethics of that hands off approach.

    We don't trust nature to take care of other problems. If someone is sick or hungry, we don't leave it up to nature to take care of them.

  6. Leaving it to nature means a lot of suffering. In such a case, I don't know which is better - to be one of the early casualties or one of the survivors who must witness the carnage.

  7. The US allows poverty far beyond any other developed nation and the the worst health system in the western world. Is the population increase across the board or restricted to the poor and religious fanatics?

  8. Good points about the US and poverty. I am disgusted about that.

    As far as religious fanatics and population growth, we are mostly made up of religious fanatics.

    In my area it is very difficult to get education regarding family planning because of the religious culture.

    When the role models are evangelists with 7 kids...