How does the Demographic Transition Model explain population changes?

The Demographic Transition Model (DTM) explains population changes through four stages of birth and death rates over time.

The DTM is a theoretical model that describes how populations change over time as a country develops economically. It is divided into four stages, each characterised by different birth and death rates, which together determine the overall population growth.

In Stage 1, both birth and death rates are high, which means the population size remains fairly stable and low. This stage is typical of pre-industrial societies where limited access to healthcare and high infant mortality rates keep the population growth in check.

Stage 2 sees a dramatic drop in death rates due to improvements in healthcare, sanitation, and food supply, while birth rates remain high. This leads to a rapid increase in population. Many developing countries are in this stage, experiencing significant population growth as they improve living conditions.

Stage 3 is marked by a decline in birth rates, which begins to balance out the low death rates. This happens as societies become more urbanised, and factors such as increased access to contraception, better education, and changing social norms lead to smaller family sizes. Population growth starts to slow down during this stage.

In Stage 4, both birth and death rates are low, stabilising the population size. This stage is typical of developed countries where people have fewer children, and life expectancy is high. The population growth is minimal or even zero, reflecting a balance between births and deaths.

Some demographers suggest a possible Stage 5, where birth rates fall below death rates, leading to a declining population. This stage is observed in some highly developed countries facing challenges like an ageing population and low fertility rates.

The DTM helps geographers understand and predict population trends, which are crucial for planning resources, services, and policies.