Nearly all of Egypt’s 110 million people live along the Nile River and its delta, while the deserts that make up more than 90 percent of the country are almost empty. A geographer studying where Egyptians live and why is analyzing

Geographers note that permanent human settlement covers only a fraction of Earth’s land surface, leaving out most of Antarctica, the Sahara, the Siberian tundra, and the high Himalayas. The portion of Earth that is permanently inhabited is called the

Bangladesh has about 170 million people living on about 57,000 square miles of land, which works out to roughly 3,000 people per square mile. This figure, total population divided by total land area, is the country’s

Egypt’s arithmetic density is relatively low, but when its population is divided only by the small amount of farmable land along the Nile, the result is one of the highest figures in the world. This second measure, population divided by arable land, is

In the United States, there are very few farmers for each square mile of farmland because large, mechanized farms need little labor, while in Ethiopia many farmers work each square mile of farmland by hand. The measure that captures this difference, number of farmers divided by arable land, is

Biologists studying an island estimate that its soil, water, and vegetation can support no more than 5,000 people at current levels of technology before the environment begins to degrade. This limit is the island’s

A region’s population has grown to the point where its farmland is exhausted, its wells are running dry, and food must be imported because local resources can no longer feed everyone. This situation is described as

A graph displays Nigeria’s population with males on the left and females on the right, stacked in five-year age groups from bottom to top; the wide base and narrow top show a very young, rapidly growing population. This graph is a

Because of a long-standing cultural preference for sons, China has about 105 males for every 100 females in its population, with the imbalance much greater among younger age groups. This figure describing the number of males per 100 females is the

Demographers describe Japan as having an “old” population because more than 29 percent of its people are over 65 and only about 12 percent are under 15. The distribution of a population across age groups is its

In Niger, about half the population is under 15, so each working-age adult must support a large number of children; in Italy, a growing share of the population is over 65, so workers must support many retirees. The measure that compares the number of people too young or too old to work with the working-age population is the

In 2023, Nigeria recorded about 36 births for every 1,000 people in its population, compared with about 11 per 1,000 in the United States. The measure being compared is the

Bulgaria records about 18 deaths per 1,000 people each year, among the highest figures in the world, largely because its population is so old. This measure is the

Demographers estimate that the average woman in Niger will give birth to about 6.7 children over her lifetime, while the average woman in South Korea will have about 0.7. The measure being compared is the

In Sierra Leone, roughly 75 of every 1,000 babies born alive die before reaching their first birthday, compared with about 2 per 1,000 in Japan. This measure is the

A baby born in Japan today can expect, on average, to live to about 84, while a baby born in Chad can expect to live to about 53. The measure being compared is

A country has a crude birth rate of 35 per 1,000 and a crude death rate of 10 per 1,000, so its population grows by 2.5 percent per year from births and deaths alone, before counting anyone who moves in or out. This 2.5 percent figure is the country’s

The same country, growing at 2.5 percent per year, can expect its population to reach twice its current size in about 28 years. This 28-year figure is the country’s

A model shows that as a country industrializes, its death rate falls first, then its birth rate falls a generation or two later, so that population growth surges in between and then levels off as both rates become low. This model is the

A related model explains that in early stages, people die mainly of infectious diseases and famine; later, as sanitation and medicine improve, people live long enough to die mainly of heart disease and cancer. This model of changing causes of death is the

In 1798, an English scholar warned that because population increases geometrically while food production increases only arithmetically, population would eventually outrun the food supply and be checked by famine, disease, and war. This argument is

A modern environmental group argues that the world’s growing population will soon exhaust not only food but also fresh water, oil, and farmland, and that the resulting scarcity will trigger conflict. Because they extend Malthus’s logic to all resources, these thinkers are called

An economist counters that history shows the opposite of Malthus’s prediction: when populations have grown, people have responded by inventing better tools, irrigation, and fertilizers, so that food output rose to meet demand. This argument is

To reverse its shrinking population, Hungary offers large tax breaks, housing subsidies, and interest-free loans to couples who have children, with the loans forgiven after a third child. This type of policy is

From 1980 to 2015, China limited most urban couples to a single child, enforcing the rule with fines, loss of benefits, and other penalties. This type of policy is

Canada admits roughly 400,000 permanent residents each year under a points system that favors younger, skilled, educated applicants, in part to offset its low birth rate and aging workforce. A government’s rules about who may enter and settle in the country make up its

Because of falling birth rates, a Southeast Asian country now has an unusually large share of its population between the ages of 20 and 50, with relatively few children or elderly to support, and its economy is booming as a result. This temporary economic boost is the

A farmer in rural Guatemala decides to leave after three years of drought ruined his crops and gang violence made his village unsafe. The drought and violence that drove him to leave are examples of

The same farmer chooses the United States as his destination because he has heard that farm jobs there pay ten times what he could earn at home and that a cousin can help him find work. The high wages and family connection that attract him are

A family leaves Honduras intending to reach Los Angeles, but while passing through Mexico they find steady work in Monterrey and decide to settle there instead. Monterrey functioned as a(n)

Migrants attempting to travel from sub-Saharan Africa to Europe must cross the Sahara Desert, pay smugglers, and then make a dangerous Mediterranean crossing in overcrowded boats. The desert, the cost, and the sea are examples of

A 19th-century study of British census data concluded that most migrants move only a short distance, that long-distance migrants tend to head for big cities, that each migration flow produces a counterflow, and that most international migrants are young adults. These generalizations are known as

A geographer predicts that far more people will migrate between Chicago and Milwaukee, two large cities 90 miles apart, than between Chicago and a small town 90 miles away, and more than between Chicago and a large city 900 miles away. The model behind this prediction is the

Between the 16th and 19th centuries, roughly 12 million Africans were captured, shipped across the Atlantic, and sold into slavery in the Americas, with no choice in the matter. This movement is the largest historical example of

After civil war broke out in Syria, a family fled across the border into Turkey because they feared being killed if they stayed, and they have been unable to return safely. Under international law, the family members are

Another Syrian family fled the fighting in Aleppo but settled in a camp in the northwest of Syria, never leaving the country. These family members are

A woman from Eritrea arrives at an airport in Germany, tells immigration officers she faces imprisonment at home for her political views, and asks to be allowed to stay; her case has not yet been decided. At this point she is a(n)

A software engineer in Bangalore accepts a job offer in Seattle, sells her apartment, and moves with her family in search of higher pay and better schools. Her move is an example of

A Filipino nurse moves to Dubai for work, sends money home every month, visits the Philippines twice a year, and keeps close ties to both countries. Her movement across an international border while maintaining connections to both places is called

Since 2010, millions of Americans have moved from the Northeast and Midwest to Texas, Florida, and Arizona, drawn by jobs, lower costs, and warmer weather. Because these moves take place within one country, they are examples of

A man from a small town in Mexico moves to Chicago, where his older brother already lives. He then helps a cousin move there, who in turn helps two friends from the same town. Over time, hundreds of people from that one town settle in the same Chicago neighborhood. This process is called

A young woman from a rural village in India first moves to a nearby market town, later relocates to the regional city of Pune, and finally settles in Mumbai, moving to a larger place each time. Her migration pattern is an example of

Hundreds of thousands of workers from Nepal and Bangladesh hold temporary permits to work on construction sites in Qatar; they may not bring their families, cannot become citizens, and must leave when their contracts end. These workers are

Each spring, herders in the Swiss Alps drive their cattle up to high mountain pastures, and each autumn they bring the animals back down to the valleys before the snow arrives. This seasonal movement is called

Every year, millions of people in China leave villages in the interior provinces to find factory and service jobs in coastal cities such as Shenzhen and Guangzhou, the largest such movement in human history. This type of migration is

Money sent home by Mexicans working in the United States totals more than $60 billion a year, exceeding what Mexico earns from oil exports and supporting millions of households in rural areas. These payments are called

Nearly one in ten doctors trained in Nigeria now practices in the United Kingdom or the United States, leaving Nigerian hospitals short of physicians even as the country paid to educate them. This loss of skilled professionals through emigration is called

In a given year, 500,000 people moved into Germany and 300,000 moved out, so the country gained 200,000 residents through migration, or about 2.4 per 1,000 people. This figure is Germany’s

After a wave of immigration, some residents of a country argue that newcomers are taking jobs, straining schools, and threatening the national culture, and a political party wins votes by promising to sharply restrict immigration. The hostility toward immigrants and the political movement built on it are known as