Population is on the increase and the world cannot contain or sustain it (Image: Michael Duva/Getty)

THINK of the biggest crowd you’ve ever been in – perhaps 50,000 in a sports stadium. Just 6 hours from now there will be that many more people in the world, and another 50,000 in the following 6 hours, and on and on… No wonder that the burgeoning human population is often seen as is the single biggest problem facing our world.

There are nearly 7 billion humans alive today, twice as many as there were in 1965, with 75 million more being added each year. UN predictions say there could be an extra 2 to 4 billion of us by 2050. The planet has never experienced anything like it.

Can the world sustain this growing horde? It’s a contentious question. While it is clear that the population cannot go on increasing forever, history is littered with dire but failed predictions of famine and death resulting from over-population. Most famously, Thomas Malthus warned more than two centuries ago that population would be held in check by rising mortality. What he failed to anticipate was the ability of newly industrialised societies to support large numbers of people.

Today, the “population problem” is firmly back on the agenda. Earlier this year the UK government’s chief scientific adviser John Beddington predicted a population-led global crisis by 2030, and a group of influential billionaires including Bill Gates and George Soros identified overpopulation as the greatest threat facing humanity. Every time we publish an article in New Scientist detailing yet another of the planet’s environmental woes, readers …