Gregory Benford - Humanity as Cancer

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GREGORY BENFORD

HUMANITY AS CANCER

" . . . still I have not seen the fabulous city on the Pacific shore.

Perhaps I never will. There's something in the prospect southwest

from Barstow which makes one hesitate. Although recently, driving my

own truck, I did succeed in penetrating as far as San Bernardino. But

was hurled back by what appeared to be clouds of mustard gas rolling

in from the west on a very broad front. Thus failed again. It may be

however that Los Angeles will come to me. Will come to all of us, as

it must (they say) to all men."

Edward Abbey - Desert Solitaire

In 1960 the journal Science published a short paper which is still

sending slow-motion shock waves through the soothsayers of our time.

Titled "Doomsday: Friday, 13 November, A.D. 2026," its abstract reads

in full, "At this date human population will approach infinity if it

grows as it has grown in the last two millennia."

Period. Its authors, Heinz van Foerster, Patricia Mora and Lawrence

Amiot, were members of the staff of the department of electrical

engineering at the University of Illinois, Urbana. They were not

population experts, but they noted a simple oddity of mathematics.

The rise in human numbers was always studied in "doubling times," the

measure of how quickly population doubled. But real human numbers

don't follow so clean an equation.

For a species expanding with no natural limitation aside from

ordinary deaths, the rate of increase of population is proportional

to the population itself. Mathematically, the population N is

described by an equation in which the change in N, dN, over a change

in time t, dt, obeys dN/dt = b N

with b usually assumed to be a constant. If b is truly constant, then

N will rise exponentially.

Fair enough. But if people are clever, the proportionality factor b

itself will weakly increase as we learn to survive better. This means

the rate of increase will rise with the population, so N increases

faster than an exponential.

In fact, it can run away to infinity in a finite time. The equation

describing this is a bit more complicated. To find how b changed with

N, the authors simply looked at the average increase over the last

two thousand years, to iron out bumps and dips, seeking the long-term

behavior.

They found a chilling result. Our recent climb in N in the last few

centuries is not an anomaly; instead, it fits the smooth curve of

human numbers. Tracking the solution backward "post-diets" that we

were a mere 9.00,000 people a million years ago. Of course such great

spans aren't well fit by population counts gathered from two

millennia, and the equation becomes silly. But it should be good for

at least a few centuries more.

Looking into the near future, it predicts a chilling result: a

singularity, with N rising faster and faster,going beyond view on

Nov. 13, 2026. "The clever population annihilates itself," they

remark laconically. "Our great-great-grandchildren will not starve to

death. They will be squeezed to death."

The paper has never been refuted. Further checks on the growth of the

factor b have pushed the singularity date further away, to about

2049. This is comforting, moving the date by about twenty years in

the thirty-four years since the paper appeared.

But the general conclusion stands. As an exercise in statistics it is

stimulating, and as far as I know the authors did little with it

after their first telling point.

Of course, nothing grows to the sky. Something will happen before b

gets too large; the four horsemen of the apocalypse will ride again.

Perhaps they already are. Still, we are not doormats. We are

attempting population control, but results are slow, and pressures

are mounting.

I wrote before in this column about the ideas which follow, in a

piece titled "The Biological Century." I'd like to revisit an idea I

floated there, with some second thoughts.

The future is coming, and it's ugly.

Or so many believe. From staid university presidents and scruffy

environmentalists alike, a growing consensus holds that humanity has

entered a watershed era, a time of vast disasters looming large, just

over the horizon of this generation. Their case rests on far more

than an equation, too.

In 1992 1 went on a cross-country hike in Orange County to protest a

highway soon to go in. Puffing up a hill, I struck up a conversation

with a member of the eco-warrior group Earth First, who wore the

signature red shirt with a clenched fist. We mounted a ridge and saw

the gray sweep of concrete that lapped against the hills below.

"Looks like a sea of shit," the Earth Firster said. "Or a disease."

That same month the National Academy of Sciences and Britain's Royal

Society jointly warned of the dangerous links between population and

environmental damage. Following this up, the Union of Concerned

Scientists mustered 1500 experts to sign a "World Scientists' Warning

to Humanity" and published it in leading newspapers. Heavy hitters,

these, including the predictable (Linus Pauling, Paul Ehrlich, Carl

Sagan), the inexpert but sanctified (Desmond Tutu], but also the

heads of many scientific societies, Nobel Laureates, and authorities

of many fields. One such Laureate, Henry Kendall of M.I.T., is

leading the New Cassandras in a campaign to muse the intelligentsia.

His case is easy to make. World population grows by 90 million yearly

and will double within half a century, maybe less. More people have

been born in the last forty years than in the previous three million

years. About 8 percent of all human beings ever born live today. We

are gaining at about 1.7 percent a year.

Meanwhile, the Green Revolution is apparently over: world per-capita

crops have declined. About ten percent of the Earth's agricultural

land area has been damaged by humans. Water may be the first major

resource to go; half of all nations now have water shortages. Even in

the American midwest and southwest, farmers are sucking "fossil

water" laid down in the ice ages, pulling it from aquifers which will

deplete within a generation.

But such policy-wonk numbers, the ecologists remind us, are too

human-centered. Our swelling numbers have their greatest impact on

defenseless species in rain forests, savannahs and coral reefs.

Biologist E.O. Wilson of Harvard warns that we could lose thirty

percent of all species within half a century, and that might be only

the beginning.

Humans exert selective pressures on the biological world. North

Atlantic waters show a clear pattern of over-fishing, and ever-shrewd

nature has filled these new niches with "trash fish" like skates and

spiny dogfish which we cannot eat and thus do not take out.

Monoculture crops worldwide gain efficiency by growing the same

staple-wheat, rice, corn, trees-over a large area, but this is

inherently more fragile. Diseases and predators prey easily and

already erosion is a major threat in many such areas.

Environmental damage grows not merely because our numbers rise, but

because our expectations do, too. The masses jammed into Buenos Aires

want a better life -- which means more consumer goods. The chain

between such ambitions and the clearing of distant forests is, though

long, quite clear.

Most environmentalists are technophobic, reluctant to admit that the

greatest enemy of the rain forests is not Dow Chemical but rather

sunburned, ambitious men newly armed with chain saws, eager to better

their lot in life.

Still, hand-wringing is not new and skepticism about it is well

earned. Paul Ehrlich's alarmist "The Population Bomb" has yet to

explode, twenty-five years after publication, though some

demographers feel that Ehrlich may simply be a few decades off.

And there are counter-trends. Many are laboring to see that the

factor b does not increase.

The "developing world" -- to use the latest evasive tag attempting to

cover societies as diverse as Singapore and Somalia-- is the great

engine of population growth, but its pattern is not an exponential

runaway. Taken all together, the poorer nations' growth rates seem to

have reached a plateau.

This may echo the industrial world, whose net growth curve broadly

peaked around 1900 at a rate of about one percent a year, and is now

a fourth of that. The poor countries may have entered just such a

transition era. Some nations began peaking in the 1970s and others

join them. Still, the plateau average rate is 2.5 percent per year,

so they have a long way to fall.

Will they decline? Environmentalists and professors alike fear they

won't.

Our numbers respond to both feedback loops and to feed-forward

anticipations. Gloom, doom- well known intellectual commodities,

finding a perpetual market. The 1960 paper is still the firmest basis

for hand-wringing. Few experts believe the planet can sustain a

population doubling in parallel with rising economic desires. This is

how the Earth Firsters merge with the academics -- a profoundly

pessimistic view of our collective future, shared from the hushed

halls of Harvard to the jerky hip-hop images of MTV.

This sea change we already see in severe cultural collision, such as

immigration. MIT's Kendall predicts a doubling of Mexico's

immigration into the USA within a decade. Shantytowns along the USA

southwestern border recall the slums of Rio. Last year the USA added

970,000 new legal immigrants, plus 132,000 refugees and the INS

estimates that slightly over a million illegal immigrants came to

stay. Our growth rate is nearly at one percent per year. Since our

native population is near the Zero Population Growth level so

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GREGORYBENFORDHUMANITYASCANCER"...stillIhavenotseenthefabulouscityonthePacificshore.PerhapsIneverwil...

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