Population

2. 18.0 Population

3. 18.1 World Population World population growth has occurred at uneven and fluctuating rates. In 2017, the world’s population reached 7.5 billion, and is growing steadily. Fun Fact! In 1970, there was roughly half the number of people in the world than there is now.

4. 18.1 World Population Before 1750, the world’s population was very slow to grow. This was a time of fluctuation, as population went up and down due to wars, famines and plagues. 1

5. 18.1 World Population From 1750 onwards, improved medical care and a better supply of food allowed the population to grow rapidly in Europe. 2

6. 18.1 World Population Over the last 100 years, population has grown rapidly, especially in developing countries. The population explosion is the result of better healthcare and food supplies generally throughout the world. 3

7. 18.2 Measuring Population Change The study of population is known as demography. We calculate world population change by measuring the birth rate against the death rate. When the birth rate is higher than the death rate, the population will have a natural increase. When the death rate is greater than the birth rate, a natural decrease in population will occur.

8. 18.3 The Population Cycle STAGE 1 A country is poorly economically developed. The birth and death rates are both very high. Countries may be experiencing war, famine and diseases. Population can fluctuate or grow very slowly. Example: Somalia

9. 18.3 The Population Cycle STAGE 2 The economy is starting to grow. Birth rates remain high, but the death rates now begin to fall because of better food, medical care and supply of clean water. Population now grows very quickly. There is a natural increase. Example: Nigeria

10. 18.3 The Population Cycle STAGE 3 The economy is continuing to grow. People begin to plan the size of their families; so, the birth rate now begins to fall. The rate of population growth slows down. Example: India

11. 18.3 The Population Cycle STAGE 4 The economy is now considered developed. Most people are living long lives, but they are having fewer children. Both the birth and death rates are now low. Population now fluctuates and only increases very slowly. Example: Ireland

12. 18.3 The Population Cycle STAGE 5 The economy is very well developed. Women are having very few children, and most people are living into old age. The population is now in decline – there is a natural decrease. Example: Germany

13. 18.4 Factors Influencing Population Change 1 Food 2 The agricultural revolution in the eighteenth and nineteenth centuries had a direct impact on population growth. 3 Factors influencing population change Machinery and new farming methods meant farmers could produce larger quantities of food. 4 The use of fertilisers improved crop production, leading to an increase in food supply and a decrease in the incidence of famine. 5 6 7

14. 18.4 Factors Influencing Population Change 1 Globalisation 2 Globalisation is the process by which the world is becoming more interconnected as a result of increased trade and movement of people. 3 Factors influencing population change People in the poorest parts of the world are becoming more aware of the wealth and lifestyle that exist in richer countries. 4 5 In developing countries, many people are being forced to move because of such events as natural disasters and war. This can cause population decreases in some regions and increases in others. 6 7

15. 18.4 Factors Influencing Population Change 1 War 2 Soldiers and civilians are killed, meaning an increase in the death rate. 3 Factors influencing population change 4 Husbands and wives are often separated, which can result in lower birth rates. 5 When soldiers return from war, some populations see a ‘baby boom’, whereby birth rates increase. 6 7

16. 18.4 Factors Influencing Population Change 1 Education 2 3 Higher levels of education can lead to a decrease in both birth and death rates. Factors influencing population change 4 The more educated people are, the more likely they will understand and take part in family planning. 5 Education also enables people to make good choices in relation to diet, personal hygiene and sanitation. This can help children to grow up healthy and live longer lives. 6 7

17. 18.4 Factors Influencing Population Change 1 Place of women in society 2 When there is equality between men and women, both sexes have equal power in making decisions about their lives. 3 Factors influencing population change In developed countries, many women will have careers outside of the home. In developing countries, women marry at a young age and will have larger families. 4 5 As these countries become more developed, women will receive better education and make choices about family planning. In turn, birth rates may decline. 6 7

18. 18.4 Factors Influencing Population Change 1 Technology 2 3 Factors influencing population change Advances in medical technology can help save lives. New medical drugs can assist people in living longer. 4 Advances in farm machinery have helped with increasing food supplies. 5 6 Water treatment equipment has helped to provide clean and safe drinking water. 7

19. 18.4 Factors Influencing Population Change 1 Health 2 3 Factors influencing population change Improvements in vaccinations and antibiotics have helped people to survive many illnesses that were once fatal. 4 Access to doctors and proper medical care have also had a positive impact. As death rates decline, populations grow. 5 6 As death rates decline, populations grow. In some developing countries, such diseases as measles and gastroenteritis (diarrhoea and vomiting) can still be fatal. 7

20. 18.5 Population Structure The population structure of a country can be displayed using a population pyramid. Population pyramids show the age–sex structure. This is the difference between the numbers of males and females as well as the number or percentage of people in each age category. A population pyramid representing the United Kingdom, 2016

21. 18.5 Population Structure Types of Population Pyramids Used to describe populations that are young and growing Usually associated with slowly developing countries Used to describe populations that are becoming old and shrinking Used to describe populations that are not growing Usually associated with developed countries Look like a typical ‘pyramid’, with a broad base and narrow top Can look like beehives Usually associated with rapidly developing countries Can have equal percentages across the age groups Narrow towards the top

22. Case Study: Population Change in a Developed Country – Ireland 13.2 Forecasting the Weather In 1841, the population of the Republic of Ireland was 6.5 million. Many people left Ireland for the United States, Britain, Canada and Australia. In the years 1845–52, Ireland experienced the Great Famine. Those who left were mainly young people, and more females than males left. More than one million people died, and a further one million people emigrated. This had an impact on marriage and birth rates. History – The Great Famine After the Famine

23. Case Study: Population Change in a Developed Country – Ireland 13.2 Forecasting the Weather Ireland is a developed country. Ireland’s population is projected to rise to 5.1 million by 2030. The population is growing slowly. The population pyramid has a stationary shape. The largest increase is predicted to occur in Dublin and the mid-east of the country. Current Population The Future for Ireland’s Population

24. Case Study: Population Change in a Developing Country – Nigeria 13.2 Forecasting the Weather Nigeria is a country located in West Africa. In 1950, the population of Nigeria was less than 40 million. There has been a rapid and large population increase over the last sixty years. It was a colony of the British Empire until 1960. Up to the late 1700s, there was an active slave trade operating out of Nigeria. History – Colonialism and the Slave Trade Nigeria’s Population in the Modern Era

25. Case Study: Population Change in a Developing Country – Nigeria 13.2 Forecasting the Weather High infant mortality: There is a need to have many babies in the hope that some will survive to work on the farm, support parents in old age and provide an income for the family. Religion: The main religion of Nigeria, Islam, promotes large families and encourages early marriage. Polygamous marriage is common. Male child preference: In many cultures in Nigeria, male children are more highly valued than females for many reasons. Security in old age: In many cultures in Nigeria, children are the only form of support for the older generations. Children are expected to take care of parents in their old age. Factors influencing population change

26. Case Study: Population Change in a Developed Country – Ireland 13.2 Forecasting the Weather Nigeria is a slowly developing country. It is estimated that by 2030 the population of Nigeria will reach 263 million. The population pyramid is expansive in shape, like a typical pyramid. Population is growing rapidly. Current Population The Future for Nigeria’s Population

27. Video: Measuring Population Change