4. With reference to a national case study, describe and explain how population structure, as shown by pyramids, can change over time. [12]

Population structure can change over time as seen in Britain. The vast changes can be shown in population pyramids.

Between 1700 and 1800, Britain had high birth rates at 37 per thousand and high death rates at 31 per thousand. This was due to a lack of family planning and contraception. High infant mortality rates also meant people were having more children to increase their chances of survival. Children were often needed to work and bring money into the home. A population pyramid would have a broad base and a similarly broad top, with only slight narrowing. Here, Britain shows a youthful population structure.

Between 1800 and 1880, Britain saw falling birth rates, however they were still high at 30 per thousand. Death rates also fell to 19 per thousand. This was as a direct result of improved nutrition and a greater availability of food resources. Improved living conditions and sanitation lead to less disease and death, along with the release of the small pox vaccine and improved healthcare. A population pyramid for this time would have a narrower base (however, still relatively broad) than previously, and and even narrower top.

From 1880 to 1950, birth rates almost halved in Britain to 16 per thousand, and death rates continued to fall to 13 per thousand. This was due to the introduction of birth control and the changing status of women in the workforce. Many delayed marriage to establish themselves in a secure job first. This also meant women were having less children in their reproductive years, with the average woman having only 2.4 children in 1921, compared to 5.5 in 1871. A pyramid would show this with a narrow base and a narrower top again. This is much the same as the previous pyramids, except the birth