World population

In humankind’s first two million years, the world population reached one billion. In the next two hundred years, it exploded to seven billion. How does the world population look now? And will it continue to grow, endlessly, in the future? Today, there are nearly eight billion people on Earth.

We can get a general picture of where they are by dividing the world map into four regions: Europe, the Americas, Africa, and Asia. If we simplify the numbers: one billion people live in Europe, one billion in the Americas, one billion in Africa, and five billion live in Asia. Experts at the United Nations expect the world population to grow more slowly over the next few decades with the population peaking in 2100 At the peak, there will be around 11 billion people in the world. Three more billion… where will they live? No more in Europe.

Almost no more in the Americas. Almost no more in Asia. These extra three billion people will almost all live in Africa. By 2100, Africa and Asia will probably have eight out of the 10 most populous countries. India will overtake China as the country with the largest population.

And Nigeria, which has one of the world’s fastest growing populations, will become the world’s third most populous country. Why is the population growing in Africa, and not much in other parts of the world? The main reason for population growth in Africa is that women here are having many children. There is a high fertility rate. In several African countries, women have, on average, five children each.

In Niger, they have an average of seven. That’s well above the global average of 2.4 children per woman. People across Africa are also living longer than ever before — just as people are across most of the world. In the last century, the average period a person may expect to live — life expectancy — has almost doubled in some countries. In India, it’s almost tripled.

And yet, increasing life expectancy alone does not mean a region’s population will grow. In Eastern Europe, for example, the population of many countries is actually shrinking. These countries are experiencing the combined effect of: a low fertility rate and large numbers of people moving away — a high emigration rate. So while people in Europe are living longer, the overall population is expected to be slightly lower in 2100 than it is today. As populations shift, the world as we know it will change.

How, exactly, we can’t be sure, but experts have some ideas. They expect that many countries that today have large, developed economies — where people are growing old and fewer babies are being born — will see the average age of their population rise. An ageing population means these countries will need to find ways to provide healthcare and financial support for the elderly. Countries with less developed economies, transformed by population booms, will face the challenge of housing, educating, and feeding more people. But their large, working-age populations could also mean more people earning money, leading to a stronger economy, and a rise in living standards.