Population bomb may be defused, but research reveals ticking household bomb

February 11, 2014

After decades of fretting about population explosion, scientists are pointing to a long-term hidden global menace.

The household. More specifically, the household explosion.

In this week's Early Online edition of Population and Environment, Jianguo "Jack" Liu, director of the Michigan State University Center for Systems Integration and Sustainability, and former students Mason Bradbury and Nils Peterson present the first long-term historical look at global shifts in how people live. One large household sheltering many people is giving way across the world to comprised of fewer people – sometimes young singles, sometimes empty nesters, and sometimes just folks more enamored with privacy.

In the late 1960s, ecologist Paul Ehrlich of Stanford University sounded the alarm about population growth. Now, Liu and his colleagues are pointing out that even though population growth has been curbed, the propensity to live in smaller households is ratcheting up the impact on the natural resources and the environment worldwide.

"Long-term dynamics in human population size as well as their causes and impacts have been well documented," said Liu, who is the Rachel Carson Chair in Sustainability. "But little attention has been paid to long-term trends in the numbers of households, even though households are basic consumption units."

More households require more lumber and other building materials. Smaller households are generally less efficient, with fewer people using proportionally more energy, land and water. Liu, with Ehrlich and others, published a paper in Nature in 2003 noting that the number of households globally was outpacing population growth between 1985 and 2000.

The latest research delves significantly further into history. Reviewing data dating back to 1600, the researches revealing that household size has been declining in some countries for centuries, adding a largely unaccounted for nuance to human's impact on the environment. In this paper, Liu and his colleagues call for households to be more centrally included in calculating human's impact on the environment, and caution against thinking that slowing population growth is a cause for celebration.

Average household size in developed countries declined rapidly from approximately 5 members in 1893 to 2.5 at present, while the rapid decline in average household size in developing nations began around 1987. The number of households grew faster than population size in almost every country and every time.

"We've documented that the changes we're seeing in household size across the globe essentially doubles the number of homes needed per-capita," Peterson said. "This will put enormous strain on the environmental life support system we rely on, even if we achieve a state of zero ."

The researchers point out that the environmental footprint becomes more of a trail. The new homes usually eventually require more roads, more yards and more commercial development.

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1 / 5 (7) Feb 11, 2014
F these screaming libs
2.8 / 5 (4) Feb 11, 2014
What a profoundly irresponsible headline. In what way is the population bomb defused, may I ask? Does this website know that not only there has been no reduction in the Earth's actual population, but that it continues to grow by about 80 million a year? That it is a relatively slower growth is merely a reflection of how gargantuan our total numbers have become. There were only 1.5 billion people at the beginning of the 20th century. We can have no clue as to whether sustaining a population of 7Bn (let alone the even larger numbers we'll grow to over the next few decades) is possible longer term. No bomb has been defused. We still have far more people than can sustainably live on this planet.
Lex Talonis
1 / 5 (1) Feb 11, 2014
We need Jesus and the plagues.

He will love us to death and the fires of hell.

And the lucky ones - who love him and his 12 boyfriends, can live in a crystal palace, in the clouds with him forever.
1 / 5 (2) Feb 12, 2014
There's a Rachel Carson chair? Wasn't she the one who wrote a bogus popular book that lead to the banning of DDT and the subsequent needless deaths of millions of innocent people throughout Africa from malaria? Looks like the anti-humanists are alive and well. Perhaps they should create a Adolf Hitler or a Joe Stalin chair too....
3.7 / 5 (3) Feb 12, 2014
There's a Rachel Carson chair? Wasn't she the one who wrote a bogus popular book that lead to the banning of DDT and the subsequent needless deaths of millions of innocent people throughout Africa from malaria? Looks like the anti-humanists are alive and well. Perhaps they should create a Adolf Hitler or a Joe Stalin chair too....

It's banned in the U.S. It has been and still is used in many counties in Africa. The mosquitoes that spread malaria become resistant to DDT, thus it becomes ineffective at preventing malaria; this has been known for decades. You probably aren't aware of Godwin's Law, but in your own ploddingly dull way, you reaffirm it.

I'm touched by your concern for the people of Africa. My suggestion is you volunteer as a human shield for some one of those innocents in Southern Sudan or Somalia or something.
5 / 5 (2) Feb 12, 2014
Typical academic myopia.

To cram the most people onto this planet we must put all the surface over to food production and house the people in boxes, preferably underground. That is where this guy seems to be heading.

But if we take the people out of the high-rise and put them in houses with small gardens, with snails and worms and spiders and sparrows and moles and hedgehogs and butterflies and bees and bats etc, etc, then the world will not be able to support as many people, but we will not risk destroying the rest of the life on this planet in the process.
not rated yet Feb 13, 2014
Whatever alfie. It's totally true though that Carson wrote a book based mostly on speculation rather than science that lead to mass hysteria and the banning of DDT at a time when it could have saved many lives.
"The panic raised by Carson's book spread far beyond American borders. Responding to its warning, the governments of a number of developing countries called a halt to their DDT-based anti-malaria programs. The results were catastrophic. In Ceylon, for example, where, as noted, DDT use had cut malaria cases from millions per year in the 1940s down to just 17 by 1963, its banning in 1964 led to a resurgence of half a million victims per year by 1969.[18] In many other countries, the effects were even worse."
not rated yet Feb 13, 2014
@gregor1 Looks like the anti-humanists are alive and well.
Nice you feel fine
not rated yet Feb 15, 2014
Let me try and explain then. Rachel Carson's book was based on speculation not science and, in leading to mass hysteria and the death of millions, is a perfect example of the law of unexpected consequences. Honoring such a person with a university chair leads me to believe that someone at least believes the death of millions was a good thing. As the cult of anti-humanism has been alive and well in the US at least since Paul Ehrlich's equally bogus popular book and the pr person who wrote this press release appears to be endorsing both books, then I believe I am justified in claiming this article is evidence that anti-humanism is alive and well.

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