GCSE Geography | Demographic Transition Model (Development Gap 5)

The Demographic Transition Model (DTM) shows changes over time in the population of a country. It is based on the changes that took place as the economies grew in western countries such as the UK.

The gap between birth rate and death rate is called natural change. This usually shows a natural increase in population but in Stages 1 and 5 a natural decrease happens.

The total population of a country responds to variations in birth and death rates (natural change). It will also be affected by migration, both immigration (people moving in) and emigration (people moving out), however this is not shown in the DTM.

As a country becomes more developed its population characteristics change. The graph below shows the general increase in level of development from Stage 1 to Stage 5.

Let’s have a look at these stages in more detail...

Stage 1 - High fluctuating

Both the birth and death rates are high, making the population total low, but fluctuating. In stage 1 there is very little health care resulting in a high death rate and low life expectancy, and no birth control, which is why the birth rate is high. The population fluctuates because of outbreaks of disease, famine and war.

Very few places around the world are in Stage 1 now with the exception of some indigenous tribes, for example, in parts of Indonesia, Brazil and Malaysia, small groups of people live separately with little contact with the outside world. They have high birth and death rates.

The UK’s population was in Stage 1 before the Industrial Revolution.

Stage 2 - Early expanding

The birth rate is high and the death rate is rapidly declining, which means the population is rapidly increasing and at some point during this stage the country will experience a population explosion. The reason this is happening is due to improved standards of living, hygiene and access to health care, which all increase life expectancy, and result in an natural increase due to the gap between birth and death rates.

Most LICs are in Stage 2 of the DTM. Even the world’s poorest countries have experienced a fall in death rate due to global efforts to tackle hunger and diseases. Afghanistan is one of the poorest and least developed countries in the world. Its birth rate is 39 per 1000 and its death rate is 14 per 1000, which has dropped hugely over the last decade. About 80 per cent of the population are farmers who need children to support them in the fields and tending livestock, which is why the birth rate is high.

The UK’s population was in Stage 2 during the early Industrial Revolution (1760-1880).

Stage 3 - Late expanding

Here the birth rate is rapidly decreasing and the death rate slowly decreasing. So the population is still increasing, but at a much slower rate. NEEs are mostly in Stage 3 of the DTM. Compared with LICs, far fewer families in NEEs still live by subsistence means. So parents do not need to have large numbers of children to help farm the land. Improved health care means that contraception may be widely available, but also independent working women in NEEs are choosing to have fewer children.

There is also the issue that children are expensive – education is not free in many countries, so families may choose to have fewer children so they can afford to send the ones they do have to school. In Bangladesh, the fertility rate is now just 2.2 children per woman on average, compared to 7 in 1970.

The UK was in Stage 3 between 1880 and 1940.

Stage 4 - Low fluctuating

This is where the UK is now, along with most HICs. Both the birth and death rates are low, with a high population that may be fluctuating slightly due to whatever’s going on with the economy, for example, people have more children if wages are high and jobs are plentiful as they know they can support them.

Access to good quality health care keeps the death rate low, and the birth rate is low as women in HICs tend to choose studying and their career over having a large family, and will usually start their family at a later age. In the UK the average age of mothers giving birth to their first child is 30.9 years, and the fertility rate is 1.56 births per woman. This means that usually in HICs the population growth is down to immigration rather than natural increase.

The UK entered Stage 4 after WW2. The birth rate increased during the 1960s economic boom and decreased during 1970s recession.

Stage 5 - Natural decrease

Here the birth rate is slowly decreasing whilst the death rate is slowing increasing resulting in a slight drop in population. People are living much longer due to improvements in health care and diet, but this increase in the proportion of older people results in an increase in the death rate. The birth rate is even lower in this stage because people have chosen to put their careers before having a family, but also periods of economic uncertainty may put people off having children temporarily.

Very few countries have reached Stage 5 – currently this is where Japan, Germany and Italy all are.