The topic of population (revisited here recently with my post on Norman Borlaug) is the subject of a special in New Scientist on "The Population Delusion". One article notes that the problem isn't population growth (which has slowed dramatically, in spite of the wailing put up by population doomers), it is our consumption patterns - Population: Overconsumption is the real problem. The edition has a column for Paul and Anne Ehrlich, still concerned about populatiuon regardless - Enough of us now.
Now the demographic monster has become a hot topic again. Yet the arguments still don't fit the reality. The population "bomb" is fast being defused. Women across the poor world are having dramatically fewer babies than their mothers did - mostly out of choice, not compulsion. Half a century ago, the worldwide average for the number of children a woman had was between five and six. Now she has 2.6. In the face of such a fall it is hard to see what more "doing something" about global population might achieve.
Half the world now has a fertility rate below the replacement level, which, allowing for girls who don't make it to adulthood, is around 2.3. This includes most of Europe, east Asia, North America and the Caribbean. There are holdouts in a few Muslim countries - but not Iran, where fertility is 1.7 - and many parts of Africa. But rich or poor, socialist or capitalist, Muslim or Catholic, secular or devout, with tough government birth control policies or none, most countries tell the same story.
This hasn't yet stopped the world's population from rising. It stands at 6.8 billion, and is growing by 75 million a year. This is mostly because the huge numbers of young women born during the 20th-century's worldwide baby boom are still fertile: they may typically only have two children each, but that is still a lot of babies. Soon, however, if fertility rates continue to decline, each generation of women will be smaller than the last.
Of course fertility rates may not continue to decline, but to date the evidence of countries that have got down to the replacement level is that they don't stick there, they carry on declining. The reasons for this may have a lot to do with the changing position of women in society. Where men take a greater role in bringing up children, and the state intervenes to help working mothers, fertility rates stay quite close to replacement. Where they do not, then super-low fertility may follow; women, in effect, go on childbirth strike.
Even if the world population does stabilise soon and starts to glide downwards, that won't solve the world's environmental problems. The real issue is not overpopulation but overconsumption - mostly in rich countries that have long since given up adding substantial numbers to their population.The key problem facing humanity... is how to bring a better quality of life for 8 billion or more people without wrecking the environment entirely in the attempt - E. O. Wilson
Take one measure: carbon dioxide emissions. Stephen Pacala, director of the Princeton Environmental Institute, calculates that the world's richest half billion people - that's about 7 per cent of the global population - are responsible for 50 per cent of the world's emissions. Meanwhile, the poorest 50 per cent are responsible for just 7 per cent of emissions. One American or European is more often than not responsible for more emissions than an entire village of Africans.
Every time those of us in the rich world talk about too many babies in Africa or India, we are denying our own culpability. It is the world's consumption patterns we need to fix, not its reproductive habits.
Ross Gittins is also talking about population growth (in a purely Australian context) in the SMH, noting that boosting GDP via immigration driven population increases misses the point - if GDP per person isn't growing, we are making citizen's (economic) lives worse, not better - Lets think twice about growth by immigration.
Over the past seven financial years, real GDP has grown by 23 per cent, but real GDP per person has grown by less than half that. So we haven't been doing as well as the headline growth figures imply.
You have to ask yourself what's so good about rapid population growth. And it's not good enough to say it makes the economy grow faster. From a narrow materialistic point of view, immigration-fed growth in the economy is good only if it raises the real average incomes of the pre-existing population.
And it's debatable whether it does. If it doesn't, we're running a high immigration policy mainly for the benefit of the immigrants, who are able to earn more in our country than in their own. Which is jolly decent of us.
Of course, if you were a business person, you wouldn't care whether high immigration led to a rise in income per person. All you're after is a bigger market because you believe it will allow you to make bigger profits.
So business believes in growth for growth's sake. Whether that attitude is shared by our politicians and economists, I'm less sure. Sometimes I think our economists are so mesmerised by Growth that they forget to inquire further.
But the other point that tends to be overlooked is that when you use immigration to force the pace of economic growth, it comes with a lot more costs attached than usual.
As the Treasury Secretary, Ken Henry, acknowledged last week, the expected continuation of high immigration raises strong questions about ''land-use sustainability and infrastructure requirements, both economic and social''.
Even so, these costs tend to be underplayed and hidden from view, partly because they're not acknowledged in our standard measure of growth, GDP. Indeed, some costs actually show up as additions to GDP. More growth - you beauty!
GDP ignores the cost of the environmental damage done by immigration. Apart from being morally dubious, poaching skilled workers from developing countries roughly doubles their greenhouse gas emissions, in the process making it all the harder for us to achieve the necessary reduction in our emissions.
So how come all those National Party and renegade Liberal politicians busy grossly exaggerating the economic cost of the emissions trading scheme have failed to mention the additional cost arising from the 6.5 million upward revision in projected population growth?
But the extra carbon emissions are just one of the environmental costs. A total projected population increase of 13 million over the next 40 years does raise the question of whether we'll exceed our ecosystem's carrying capacity.
Is the additional land use sustainable? Here's a country that badly stuffed up its river and underground water systems, and as we speak is demonstrating a serious lack of political will to fix the problem, telling itself an extra 13 million people will be no probs.
And what about the cost of all the roads, hospitals, schools, police stations and untold other infrastructure we'll need to build to accommodate a 65 per cent increase in the population? All that spending will add to growth as measured by GDP, but that doesn't mean it won't come at considerable cost to taxpayers.