Earth's 6 billionth baby will be born this year

In all the hoopla over the approach of a new millennium and the Y2K crisis, another imminent milestone for the planet has received relatively little attention: Y6B, the year of 6 billion.

Sometime in the near future -- the U.S. Census Bureau estimates the date as July 19, while the United Nations pegs it at Oct. 12 -- a baby will be born somewhere on the globe, pushing world population over the 6 billion threshold.

Even in an era of trillion-dollar budgets, mega-billionaires, and an 11,000 Dow, the 6 billion figure is staggering, especially when placed in perspective. It took all of human history up to 1804 just to reach a global population of 1 billion. It took just 12 years to leap from 5 billion to 6 billion.

The world's population grew by just 600 million in the 19th century. It grew by 4.4 billion in the 20th century. There are twice as many people today as there were in 1960 and the population is still growing. Even assuming a continued decline in fertility rates, the U.N. projects a population of 8.9 billion in 2050. Under current trends, world population isn't projected to stabilize until some after 2080.

Consider that the Earth gains 78 million people annually, roughly the equivalent of adding a new France, Greece and Sweden combined each year, or a city the size of Philadelphia every week.

In 1800, London was the world's largest city with 1 million people. Today, 326 metropolitan areas have more than 1 million people and 16 cities have more than 10 million. By 2025, there are expected to be 650 cities with populations of more than 1 million.

The 21st century is expected to be the first century in which the majority of the world's people live in urban rather than rural areas.

Ironically, population and family planning experts worry about a growing complacency in some quarters even as the world breeches the 6 billion threshold. A remarkable decline in fertility rates has made family planners in some ways victims of their own success.

As a result of efforts begun in the 1960s and '70s, annual world population growth appears to have peaked at 86 million in 1989. Average global fertility has been halved, from a high of about six children per woman in the 1950s to 2.9 per woman today. There is not a single industrialized nation in the world with a fertility rate above replacement level, which is about 2.06 children per woman.

Indeed, the United States, with 2.03 children per woman, has the highest fertility rate in the developed world. The average fertility rate for European countries is 1.4. In Japan, it's also 1.4. Even in some developing nations -- South Korea and Taiwan, for example -- the rate is at or below 1.6.

In the Third World, where 98 percent of future population growth is expected to take place, there have also been dramatic declines. The average fertility rate for developing countries, excluding China, is now 3.8.

"Demographers have been repeatedly amazed at how rapidly fertility rates have come down in a matter of few decades," said Brian Halweil of the Worldwatch Institute.

However, slower growth is a long way from no growth.

"We've come halfway," said former U.S. Census Bureau director Martha Farnsworth Riche. "The danger now is that we will declare victory and go home."

In Africa, the Middle East and southern Asia, fertility rates remain high. In 40 African nations, women still average six children. Niger leads the world with 7.5 children per woman. And Latin America is still growing, albeit more slowly.

But the main reason world population will continue to grow rapidly for decades despite slowing fertility rates is something population experts call "demographic momentum." There are over 1 billion people ages 15 to 24 in the world already and nearly 2 billion under age 15, most of them destined to become parents. In the developing world, more than a third of the population is under age 15.

China is the world's most populous nation with 1.28 billion people. But next spring India is expected to become the world's second nation with more than 1 billion people and will surpass China sometime before 2050.

Africa, with 13 percent of the world's population, is projected to see 34 percent of the globe's population increase over the next 50 years. India and China combined will account for another 25 percent of the increase.

The current U.S. population is 272 million, making it the world's third most populous country, and it is projected to grow to 335 million by 2025. Most U.S. population growth is due to immigration and lower mortality rates. Life expectancy in the U.S. has risen from 47 years in 1900 to 77 years today.

One result of increasing population pressures is that the world is currently in the midst of a mass extinction unequaled since the disappearance of the dinosaurs 65 million years ago, according to the Worldwatch Institute.

Working with more than 600 scientists, the World Conservation Union published a survey in 1996 estimating that one-fourth of all mammals and amphibians, one fifth of all reptiles, more than one-third of all fish and 11 percent of birds are in danger of extinction.

Life-threatening water shortages are increasingly likely in some parts of the world, environmentalists warn. In India, which adds 18 million people a year, water tables are dropping 3.3 feet to 9.9 feet a year. The result could be less water for irrigation, cutting India's grain harvest by one-fourth and increasing hunger and malnutrition, according to the Worldwatch Institute.

Meanwhile, some scientists are warning of an emerging demographic divide between countries whose birth rates are falling and countries whose death rates are climbing.

While advances in health care and technology have increased life spans in this century an average of roughly 20 years worldwide, the AIDS epidemic has caused life expectancy in some African countries to plummet in recent years.

In Botswana, life expectancy has fallen from 62 years in 1990 to 44 years in 1998. In Zimbabwe it has fallen from 61 years in 1993 to 49 years in 2000. For the first time since famine claimed the lives of 30 million Chinese in the late '50s and early '60s, rising death rates are slowing world population growth somewhat.

Efforts by family planning agencies to empower women and to increase access to contraception -- which reduces the spread of AIDS as well as lowering fertility rates -- continue to meet resistance from Islamic nations and the Catholic Church.

The Vatican has accused the U.S. and other western nations of "biological colonialism" for their efforts to bring contraception to the Third World. Ironically, some of the lowest birth rates in the world are in predominantly Catholic countries like Italy and Spain (1.2), Portugal (1.5), and Ireland (1.9).

(Joan Lowy is a reporter for Scripps Howard News Service.)