Everybody talks about population growth, but little attention is paid to an inevitable byproduct of that problem -- the growing number of dead bodies. Limitations of space, environmental concerns, local laws, even larceny complicate attempts to resolve the situation, according to PNS commentator Walter Truett Anderson. Anderson, author of "Evolution Isn't What It Used To Be" (W.H. Freeman), is a political scientist who writes widely on technology and global governance.

With all the worry about the planet running out of room, it may be time to start thinking about the other face of the population explosion -- finding space for the dead.

We have been hearing for a long time now that the world is getting more crowded -- Thomas Malthus first sounded the warning some 200 years ago, and more recently environmentalists and doomsayers such as Paul Ehrlich have taken up the call.

And indeed global population has soared. Starting at around five million several thousand years ago, passing 500 million in the seventeenth century, currently pushing six billion and likely to double in the next few decades.

Most of the warnings and projections, of course, have to do with living people, the ones who must be housed and fed and employed. Nobody is paying much attention to the increasing numbers of the dead -- but their numbers grow right along with the numbers of the living, and they are, in their own way, a social obligation as well.

In many parts of the world, this is becoming a serious problem. Existing graveyards are running out of room, and growing pressures on land -- from urban growth, highway construction and expansion of agriculture -- make it difficult for communities to find space for new ones. The pressure is so great in some places that developers have callously taken over former graveyards for other purposes.

At the same time, considerations of ecology and public health often prevent people from continuing traditional practices such as floating dead bodies down rivers or taking them to open areas to be consumed by scavenging animals and birds.

In the West, cremation is more and more often the preferred solution -- not outdoor cremation on a funeral pyre, as practiced in India and some other countries, but rather indoor cremation in the "crematoriums" that have joined mortuaries and mausoleums as features of the modern death industry.

The practice of indoor cremation began only a little over a hundred years since the practice of indoor cremation began, but today -- according to "Grave Exodus," a recent book on this somber subject -- cremation is an increasingly popular option among Americans, especially in the big cities, less so in the more rural and conservative Bible Belt.

Cremation is generally followed by storage of the "cremains," as they're now called, in a "columbarium" -- literally a pigeon house -- a structure with many recesses though for urns instead of birds. Some of the columbariums themselves are now becoming rather crowded -- one in the New York City borough of Queens now has over 50,000 urns, though this obviously a space-saving alternative compared to 50,000 graves.

Another option -- even more economical in terms of space -- is to have the ashes scattered from an airplane or a boat at sea. This is the alternative offered, at a cost considerably below that of the fancier American procedures, by organizations such as the Neptune Society.

But even ash-scattering, resolutely sensible as it may sound, has its problems. For example, some state and county governments have laws restricting dissemination from an airplane, meaning that the Neptune Society option is for the most part available only to people living near an ocean.

Another problem is that, in death as in life, you can't always be sure you will get what you paid for. Not long ago there was a considerable scandal concerning a private operator -- a freelance pilot who had been making a substantial living as an ash-scattering subcontractor to a number of funeral homes. It turned out that the pilot had not been scattering the ashes as promised but stashing them in a storage locker, where some 5,000 boxes of cremains were found. The pilot himself committed suicide, thereby adding yet one more to the world's ever-growing supply of deceased human beings.

Despite such difficulties, in the long run -- if human population continues to increase -- cremation and the scattering of remains will likely emerge as the preferred solution everywhere.

But will human population continue to increase? The answer to that comes in two parts -- birth rates and death rates. If birth rates continue to decline, as they are doing now in many parts of the world, the total number of humans will level off and could begin to decline sometime early in the next century. If this happens, many population-related problems -- including what to do with the dead -- will become less intense.

On the other hand, if death rates decline -- which they will if human life expectancy increases dramatically, as many futurists are now predicting -- the population will continue to grow. Some science-fiction writers, carrying this prediction to its logical extreme, describe a future in which people live for centuries, and the human population expands to fill all inhabitable planets of the solar system as well as various moons and asteroids.

In those scenarios, decisions about what to do with individual dead bodies are postponed, but the overall problem is not solved. The dead, like the poor, we will always have with us.