Updated 10 July 2013

7.2 billion... and counting

"Population explosion" used to crop up often in the media. Now we’re hearing how countries are fretting over falling birth rates. Was the population bomb a damp squib?

The simple answer: No. But population remains a confusing and controversial topic, plagued by misconceptions. So let's clear up some of the more common:

Myth 1: World population has stopped growing
Global population has now reached about 7.2 billion. The latest projections expect the figure to rise to around 9.6 billion by the mid-21st century. That’s an increase equivalent to the populations of China and India combined!

Population has not stopped growing: we are positively bursting at the seams. What has changed is the rate at which population is growing.

In the 1960s and 70s, many demographers expected world population to continue to rise exponentially i.e. shoot up and up like bacteria multiplying in a Petri dish, until the inevitable crash when resources were exhausted.

But the current scientific consensus is that global population growth has started to slow down compared with a few decades ago; it will start to level off and possibly start declining in the late 21st century.

The current growth rate for world population is about 1.1% annually. That still equates to a huge number however: about 70 million more people added to the earth each year.

Another important consideration is that, even though growth rates have slowed overall, they are still high in many less developed countries, which means these populations are still increasing rapidly.

Many countries have birth rates above the "replacement rate" of two children per woman. Also, because of even higher birth rates in the past, many nations have large numbers of young people moving into their reproductive years.

Myth 2: Overpopulation is the 3rd world’s fault
Firstly, many women and girls in third world contexts have little choice about how often they become pregnant.

Women with low socio-economic status, who lack access to education, family planning and contraception, often first become mothers when they are barely out of childhood themselves.

Secondly, people living in poverty tend to have more children, as under these conditions infant mortality is still commonplace and there isn’t access to insurance or retirement funds to guard against death and disability. Parents often have larger families if they fear their babies may die, when they need labour for the family farm or business, and to ensure they will be cared for in old age.

Myth 3: Wars and diseases like Aids will curb population growth
Relying on an increased death rate to solve overpopulation is absolutely unacceptable in humanitarian terms, yet it is extraordinary how often this viewpoint is expressed – particularly as regards HIV/Aids.

Disease and violence does impact on population numbers, but not to the extent that it is causing a negative world population growth rate. This has only ever happened once that we know of in the history of the human race, when the Black Death (likely bubonic plague) ravaged the populations of Europe and Asia in the 14th century.

There are other aspects to disease epidemics and wars that complicate the population picture. HIV/Aids is expected to bring about socio-economic slowdowns in many third world countries hard-hit by the disease, which in turn may cause people to have more children.

Myth 4: It’s fine to have a big family if you're rich
Mel Gibson has seven kids, but that’s fine because he can certainly afford to give them a good life. Right?

Your financial status is an important factor in planning the size of your family. But it’s just one issue.

Each child born on the planet will make demands on its resources – water, food, energy, space – and will have an environmental impact in terms of land used to access these resources, and pollution produced from fossil fuel use.

So, the more children you have, the greater their resource consumption and negative impact will be.

But it’s not just how many children you have – it’s who they are and where they live.

A child born to a poor family in Bangladesh, say, will consume far less of his or her share of global resources than a child born into an average American household. The first world uses over five times the energy per capita used by the third world.

Myth 5: Rich countries must breed or face failing economies
In some developed countries and a few developing ones, the fertility rate has dropped below the replacement rate of two children per woman. This means that, if there is no further immigration into these countries, their population numbers will eventually start to decline, potentially leading to economic stagnation.

But a call to young well-off people to "go forth and multiply" is hardly a solution. It is most unlikely that young women in developed countries, who are better educated and more empowered than previous generations, will revert to being baby-making machines at the expense of their freedom and careers.

Besides which, the world doesn’t need more "superconsumers" i.e. first world children consuming resources at current rates.

Myth 6: The planet can handle many more of us
If human life is precious, then surely more human lives would be a good thing?

The indications are, however, that as the population continues to grow, more human lives are lived in misery. To look at just a couple of the dismal stats:

  • More than half of the world's people live below the poverty line.
  • Nearly one third of people in rural areas lack access to safe drinking water.

Thus there are strong arguments for the case that we can’t handle 7 billion people – let alone 9 billion.

Ecology tells us that a population of organisms can only continue to thrive as long as it doesn’t use up the resources that sustain it faster than these can be replaced. The maximum number of creatures an environment can support without becoming degraded is known as its carrying capacity.

And there are signs everywhere – global warming and other forms of pollution, desertification and deforestation – that we are approaching the carrying capacity of the planet; in fact, we may have already exceeded it.

The way forward
One great lesson learned from population ups and downs (fewer of those) over the last hundred years is that by far the best way to stabilize populations to their benefit is through humanitarian intervention – with a strong focus on women.

Success stories from around the globe of populations stabilising have been because people (especially women) have better access to primary health care and family planning services, receive at least a basic education (especially girls), and have government services to protect them when they can’t work.

As for developed countries facing a "birth dearth", the obvious solution, both practical and humanitarian, lies in facilitating immigration from countries struggling with overpopulation, which needs to be viewed as primarily a global, rather than a national, problem.

Population Reference Bureau, 2012 World Population Data Sheet
United Nations World Population Prospects 2012 Revision


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