A Growing Population 6.1

World Population  The total number of people on Earth  More than 6.4 billion  By the year 2050, the world population could be more than 9 billion  Meeting the needs of all these people has a huge impact on Earth’s natural environment

Growth Rates  The world population grows by about 85 million people each year  233,000 people are added each day (about 10,000 per hour, 3 per second)  The growth rate is how quickly a population increases or decreases

Adding to population  People are added through births  People are subtracted through deaths  People can be added/subtracted through migration  A large movement of people from one place to another

Exponential Growth  Read page 217  Persian Legend pg 218  Carrying capacity – The largest number of living things that an area can support  Earth’s estimated carrying capacity is billion people

Understanding Numbers  Population growth is tied to two factors – Birth rates and death rates  Problems such as food shortages and diseases increase death rates  Death rates are the numbers of deaths in one year per 1,000 people

Numbers cont.  Medical discoveries and technologies increase birth rates  Birth rates are the number of births in one year per 1,000 people

Early Life  Early hunter-gatherer population numbers were quite small due to the challenges of finding food and staying alive  Population did not increase until the Agricultural Revolution  Food was easier to obtain, people lived longer and produced more children

Population grows  Another jump in the population was due to the Industrial Revolution  Improvements in medicine and food production made people less likely to die from sickness and hunger  Death rates decreased and birth rates increased  This pattern continued for many years

Recent Decrease in Population  The world’s growth rate has slowed some in the last years  Women in many parts of the world are choosing to have fewer/no kids  Diseases such as AIDS are increasing death rates in many areas

Vocabulary  World Population  Growth Rate  Migration  Carrying Capacity  Death Rate  Birth Rate