According to most estimates the world’s population has just hit - or is just about to hit - the seven billion mark. A United Nations estimate has the world’s population peaking at about 9.3 billion in the middle of the century. That’s roughly a third as many human beings on the face of the planet 40 years from now as there are today, and that’s going to present nations already straining to meet the resource challenges of the 20th-century population boom with all kinds of additional challenges. Add to that the task of decoupling the global economy from fossil fuel and Houston, as they say, we have a problem.
The world’s human population only hit the one billion mark around about the time a young Queen Victoria acceded to the throne. It took an another century to hit the second billion. Billion three took 35 years, the fourth a mere 15, and for a while there it looked like we were going to breed ourselves to kingdom come. Then the rate of growth began to slow. China’s one-child policy began to kick into gear. Education and birth control began to reverse the trend in some countries. Others, like Nigeria, the Philippines and Indonesia, began to recognise the crippling effects of a surging population. After peaking at just over 2.1% in 1971, the world’s population growth rate slowed to just 1.2% in 2009 (this graph lets you plot the growth rate of just about every country).
It’s not all one-way traffic, however. Many countries face the opposite problem: population decline. This table indicates most countries facing population declines are characterised by a strange combination: high education and mounting poverty. Nations in Eastern Europe and the former Soviet Union benefited from excellent education and health systems during the Cold War, leading to high life expectancy rates and low birth rates. High levels of education tend to result in lower birth rates - birth rates so low they are deemed sub-replacement fertility rates (SRFR). An SRFR means simply that more people are dying than are being born. In developed countries, the SRFR is about 2.1%. In developing countries where life expectancy rates are lower (in Swaziland, which has the lowest life expectancy in the world, it’s just under 40 years), the SRFR can be as high as 3.4%.
The end of the Cold War has impoverished many former Eastern Bloc countries, lowering life expectancy rates and encouraging emigration. For developed countries, immigration can mitigate a sub-replacement fertility rate - but who wants to emigrate to a poor country that’s only getting poorer?
The Wheeler Centre is hosting a panel discussion tonight in partnership with ABC Radio National on population called ‘Seven Billion: It’s Getting Hot in Here’, hosted by Natasha Mitchell.