1. Chapter 4 Section 1 In 1950 New York was the only metropolitan area in the world with a population over 10 million. By 1994, 14 world cities had populations greater than 10 million. Four of these cities were in economically developed countries; the rest were in countries still developing modern economies. By 2015 experts predict that the population of the following cities will exceed 20 million: Tokyo, Mumbai, Lagos, Shanghai, Jakarta, São Paulo, and Karachi. Of these cities only Tokyo is in an economically developed country.

2. Population Growth The population of Earth is now about 6 billion and is expected to reach 7 billion by 2010. People inhabit about 30 percent of the planet’s land.

3. Growth Rates World population is growing rapidly because birthrates have not declined as fast as death rates. Improved diet and health care have lowered the death rate in many places. In economically developing countries, the birthrate is often very high. Wealthy industrialized countries, however, tend to have a low birthrate

4. Challenges of Population Growth World food production has risen to meet demands on every continent except Africa. However, rapidly growing populations still face shortages of freshwater, housing, and clothing.

5. Negative Population Growth In some countries the death rate is higher than the birthrate. Countries with negative growth rates often recruit workers from other countries to supplement their workforce.

6. Population Distribution Population Density The earth’s people are not evenly distributed over the available land. Most people live near sources of freshwater and in areas where the climate is temperate. Population density measures the average number of people living on a square mile or square kilometer of land.

7. Population Movement More and more people throughout the world are moving to urban areas in search of better jobs, education, and health care. About half the world’s people now live in urban areas. People also migrate from one country to another, seeking greater economic opportunities and political freedom. 3.3 analyze factors that influence human movement and settlement patterns