The List: Five Population Trends to Watch

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Europe and Asia Turn Gray

Where its occurring: Europe, Japan, South Korea, and Singapore

Whats happening: Couples are having fewer babies than they used to. In Italy, for example, the total fertility rate is 1.3 children per woman, and in Japan it is just 1.2. As people have fewer babies and as baby boomers hit their rocking chairs, senior citizens will make up a larger fraction of the population, while working-age adults will make up a smaller fraction of the population. By 2050, people 60 and older will comprise 39 percent of Italys population and 44 percent of Japans. The result: There will be fewer workers to pay each elderly persons healthcare and social security costs. Unless working adults are taxed more or benefits for seniors are cut, governments budgets will go bust.

Whats being done about it: Governments are trying to get people to have more babies. In Singapore, matchmaking services are provided by the governments Social Development Unit, while in Japan local governments are sponsoring speed dating. One Russian province offers entices couples with time off from work to conceive babies on its annual Conception Day. Baby bonuses are also popular. Germany now gives parents two thirds of their previous years income when they stay at home during a babys first year. Spains prime minister recently proposed giving families 2,500 euros ($3,500) for each baby produced. And, of course, European countries are well known for giving mothers various levels of paid maternity leave.

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The Global South Explodes

Where its occurring: Developing countries in Africa and Asia

Whats happening: Poor and uneducated women tend to have more children. Many such women live in developing countries, and over the next few decades thats where most of the worlds population growth will occur. Just 23 years from now, in 2030, Ethiopia will overtake Russia in population, according to United Nations projections, and Uganda will overtake Germany in 2040. At a minimum, rapid population growth could strain countries with weak infrastructures if roads, sewer systems, schools, and health services cant keep pace with demand. At its Malthusian worst, rapid population growth could lead to scarcity of food and fresh water, environmental destruction, filthy disease-filled slums in megacities, and, some say, even outright war.

Whats being done about it: Many nongovernmental organizations want to increase access to contraceptives, but resistance often comes from religious leaders and governments. Some have suggested that family planning is part of a Western plot to keep Muslim and dark-skinned populations in check. Meanwhile, the U.S. government has been criticized for its so-called global gag rule, which denies U.S. assistance to foreign nongovernmental organizations that engage in certain abortion-related activities. But this debate over contraceptives could be moot. Birthrates tend to fall as women become more educated and as societies become wealthier: South Koreas fertility rate plunged from 6.3 children per woman 50 years ago to 1.3 today. So perhaps the best contraceptive is teaching girls to read and promoting economic development.

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AIDS Decimates Sub-Saharan Africa

Where its occurring: Botswana, Zimbabwe, Swaziland, and Lesotho

Whats happening: HIV-AIDS is wiping out Africans in their prime working years, when they would otherwise be contributing most to the economic development of their countries. Between 1992 and 2004, 31 countries in sub-Saharan Africa lost an average of 0.7 percentage points of economic growth per year because of HIV-AIDS, the International Labor Organization estimates. By 2020, 23 sub-Saharan countries will have lost more than 9 percent of their working-age populations, with Botswana, Lesotho, Swaziland, and Zimbabwe losing over 35 percent of their workforces. With able-bodied working-age adults dropping out of the population, who will be there to teach children to read, grow food, work factories, run government agencies, and keep the economy going?

Whats being done about it: Governments, businesses, and private individuals around the world are donating money to stop the spread of HIV-AIDS. For example, the Global Fund to Fight AIDS, Tuberculosis and Malaria, which has received $4.7 billion since 2001, finances programs that are implemented by local experts. Last year, UNITAID was founded to provide AIDS drugs and other medications to people in developing countries by using revenues from taxes on plane tickets. The strained governments of AIDS-afflicted countries have also been showing signs of becoming more serious about stopping the disease. Its an uphill climb, thoughone that relies on improving governance, raising awareness of how HIV is transmitted, getting drugs to infected people, distributing condoms, raising the status of women, and reducing social stigma.

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Too Many Grooms, Too Few Brides

Where its occurring: China and India

Whats happening: In China, a strong preference for sons and the countrys one-child policy mean that 118 boys are being born for every 100 girls. In India, a tradition of crushing dowries and the need for a son to support parents in old age have contributed to a gender imbalance as high as 120 boys per 100 girls in some parts. When these boys grow into adults, it could set off a testosterone time bomb of sexually frustrated young men who cant find partners. China projects that in 2020 it will have 30 million more men of marriageable age than women.

Whats being done about it: To reduce abortions of females, China and India have banned using ultrasound machines for determining the sex of a fetus. That hasnt stopped the gender imbalance, however. For the right price, ultrasound technicians will find ways to tell expectant parents what they want to know. A better solution could lie in turning Indian and Chinese girls from economic liabilities into economic assets. The Indian state of Tamil Nadu, for instance, introduced a Girl Protection program in which the government opens a bank account upon a girls birth and deposits money in it during her childhood.

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The South Heads North

Where its occurring: The United States and parts of Europe

Whats happening: Demographic fault lines are developing where rich and poor populations abut one another. Each year, Mexicans cross into the United States illegally, in search of the American dream, with an estimated 485,000 entering illegally each year from 2000 to 2004, according to a Pew Hispanic Center report. Due largely to immigration, Hispanics will comprise 24 percent of the U.S. population by 2050, up from 13 percent in 2000. Non-Hispanic whites, meanwhile, will make up only 50 percent of the population by 2050. On the other side of the Atlantic, North and West Africans are leaving behind the ballooning populations in their home countries and taking extreme risks to reach Europe. Last year, 32,000 reached Spains Canary Islands en route to the European mainland, and an estimated 6,000 died by drowning or malnourishment while crossing the waters. Receiving countries worry about rapid changes in the ethnic composition of their populations and the cultural changes that it can bring.

Whats being done about it: When U.S. President George W. Bush proposed a guest worker program earlier this year, his initiative died due to controversy over whether to grant effective amnesty to the millions of illegal immigrants already living in the country. Meanwhile, some local communities are growing frustrated with the federal governments inability to enact reform. The town of Hazleton, Penn., for example, last year passed a group of measures, since struck down by the courts, that included fining landlords who rented to illegal immigrants. Meanwhile in Europe, countries have looked for ways to promote economic development in Africa as a way to stem the tide of illegal immigrants. In addition, Spain and Italy, which are entry points for many Mediterranean-traversing immigrants, have beefed up sea patrols.

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