It took only a little over a century for the worlds population to reach two billion in 1930. The third billion was added after 30 years and the fourth after 15 years. Today, another 2 billion people have been added since 1975, and projections indicate that at the current rate of increase, world population will double again in just 47 years.
However population growth has not always been steady. Famine, war or disease often decimated local cultures. In fact, as population grew, another pattern of human history emerged that of overpopulation, which has led to over-exploitation of resources.
Despite these setbacks, however, population continued to grow overall. On the eve of the industrial revolution in 1750, humans numbered around 750 million, and just after 1800, world population reached one billion.
Despite the fact that global birth rates have declined in recent years, population increases will continue for the foreseeable future because of a factor known as population momentum. This means that even if people have fewer children on average, there are so many more people having children overall that population continues to grow. Today, roughly one third of the world's population - nearly two billion people -are under the age of 15. As those young people - most of who live in LEDC’s – will start families in the future, and the world’s population will explode.
The opinions of scientists, politicians, and citizens are deeply divided as to what the future holds. But the two main theories are that of Boserup and Malthus.
There are two main theories relating to population growth and resources. These theories are the Malthusian theory and Boserup’s theory. They offer their own different interpretations of the relationship between world population and resources, Malthus giving a pessimistic view and Boserup a positive view.
Thomas Malthus devised the Malthusian theory in 1798. It offers a pessimistic view over the dangers of over-population and states that it would eventually lead to a shortage of food on a global scale, poverty, hunger and disease.
He believed that human population increases geometrically (i.e. 2, 4, 8, 16, etc.) whereas food supplies can only grow arithmetically (i.e. 2, 4, 6, 8, etc.) as it is limited by available land and technology. The geometric population growth outruns an arithmetic increase in food supply. He stated that the ‘laws of nature’ dictate that a population can never increase beyond the food supplies necessary to support it.
Malthus was an 18th century clergyman and believed that population growth was caused by lack of moral restraint and he advised delayed marriage and abstinence from sexual relations.
Contrary to this, Boserup believed ‘necessity is the mother of invention’. She asserted that an increase in population pressure acts as an incentive to develop new technology and produce more food. Her theory concluded that population growth naturally leads to development.
So the theories can both be correct, depending on your personal point of view. My personal view is that malthus’ theory is correct to begin with, and the will be a period of time on earth where the populae will experience extreme hardship. However, after this, as Boserup predicted, the human race will adapt to the pressures of the situation, and once again the worlds’ population levels will drop, and the situation will continue in a cycle.
