37. OVER-POPULATION

by Dr A. S. Parkes

The essential fact about the population problem is well known. It is simply that world population is increasing at a rate with which food and other production may not be able to keep pace. World population is thought to have increased by 1,000 million since 1900 - that is, by more than 60 per cent. The total, now thought to be approaching 3,000 million, is not, of course, equally distributed in proportion to the land areas. Europe, including the USSR, is about averagely populated, Africa, North and South America and Oceania are under-populated, and Asia is greatly over-populated. The rate of increase is also very uneven. In Singapore a very high and almost static birth-rate, coupled with a rapid decline in the death-rate, is giving rise to serious alarm. Many other regions, such as Malaya, Ceylon and Mexico, are in the same position to a greater or lesser extent. In Great Britain a death-rate which is not particularly low com bines with a low birth-rate to give a very small rate of increase. Those Asian countries in which the rate of increase is still slow are being held back by a high death-rate rather than a low birth-rate, and the same applies to Africa.

The growth of world population has not been caused by a sudden increase in human fertility, and probably owes little in any part of the world to an increase in birth-rate. It has been caused almost entirely by advances in the medical and ancillary sciences, and the consequent decrease of the death- rate in areas where the birth-rate remains high. It is illuminating to consider the impact on population growth of even a single discovery in medical science. DDT is an outstanding example. The story of DDT as an adjunct to public health campaigns began in 1945, when two members of the Institute of Tropical Agriculture in Trinidad spent a weekend in British Guiana. The Health Officer reported that the extremely high infant mortality-rate of 250 or more was due largely to insect-borne diseases. They told him of DDT. Shortly afterwards, he was able to get enough to spray by airplane a 10-mile area, including the city of Georgetown. Results were instantaneous. By 1948, the infant mortality-rate dropped to 67. As a result, that small area had one of the most rapid rates of population increase ever recorded. With present birth-rate and death-rate trends, the world is threatened with astronomical numbers of people. To quote from the preface of a United Nations report, The Future Growth of World Population (1958): ". it took 200,000 years for the world's human population to reach 2,500 million. It will now take a mere 30 years to add another 2,000 million. With the present rate of increase, it can be calculated that in 600 years the number of human beings on Earth will be such that there will be only one square metre for each to live on. It goes without saying that this can never take place, something will happen to prevent it." The human race will have to decide whether that "something" is to be pleasant or unpleasant.

Two lines of thought are often advanced in support of the view that the population problem can be solved without conscious limitation of numbers. It is argued that the intensive application of scientific methods to production and distribution could increase food supplies and other resources ' sufficiently to provide not merely subsistence, but an improved standard of living for the world's rapidly increasing population. This easy view is not shared by those responsible for policy in countries such as India, where increases in population swallow up the increases in production which could otherwise be devoted to improving the standard of living. In any case the argument based on an indefinite increase in production inevitably breaks down at the vision of standing-room only on the planet Earth.

It is necessary, therefore, to introduce a corollary, that with an improved standard of living, the birth-rate will fall spontaneously in other parts of the world as it has done in Western Europe during the present century. This argument, too, breaks down. It is easy to say that people come to prefer motor-cars to babies, but how is this preference to be implemented? This question answers itself; evidently voluntary control, by whatever means, must have been a large factor in the decrease in the birth-rate in Europe during the last 50 years. Secondly, it seems that what has become known as the demographic cycle works both ways and that with a very high standard of living there are both motor-car and babies as in the USA.

If, then, it is unsafe to rely on increased production and demographic trends without conscious control to solve the problem, what remains? Medical science is largely responsible for creating the problem and can reasonably be expected to take a large share of the responsibility for solving it.

(from New Scientist, 8th June, 1961)