The seventh billionth person on Earth is waiting to be born. Somewhere on our planet on October 31st he or she will arrive, one of the 358,000 births on that day, on every day. We do not know where the birth will occur, but it will be unheralded, a routine event probably in the shantytowns of one of the growing Asian megacities. The prospects for that child will be poor.
In the millions of years since the human journey began when we separated from a common evolutionary branch with the apes, we have been lucky to survive. Most of the time we have struggled for existence, half starving, with most people barely living beyond their teens. There were times when famine and natural catastrophe dwindled our numbers to a few thousand and threatened our extinction. But we survived, and since the end of the last ice age have flourished in almost all areas of the globe and our numbers have grown as we invented agriculture and civilisation. Looking back on our evolutionary journey there are behind every living person on Earth 15 ghosts. Six percent of all the humans who have ever lived are alive now.
When the seventh billion person arrives he or she will join a exclusive club whose members are unknowable. They were born in 1800, 1930, 1960, 1975 and 1987 and 1999.
The human population reached one billion in 1800 when a child was born into a world rife with revolution. Then the billions came at an ever-increasing rate. The two billionth person is 81, born in an era of depression and rumours of war. The three billionth is 51, born into a decade of change, the start of the space age and the Cold War. The four billionth is 36, born amid the 'me' decade. The fifth is 24, having arrived when the newly industrialised nations were emerging, and the sixth is aged just 11, and when learning to walk entered the post 9/11 world. With the exception of the one billionth person they may all be still alive. Theoretically they could all meet.
Every 24 hours on our planet some 358,000 people are born and 155,000 die. Of course they all require space and resources. Can the Earth can cope with them?
It was question that occurred to an English cleric, Thomas Robert Malthus, more than 200 years ago. He believed that human population growth would outstrip the Earth's carrying capacity and that disease and famines would limit humanity's growth. Some believe that it may happen like this, that the human population is already at three times the sustainable level and that we should aim to reduce the global population to that of 1930. However, the statistics do not support this view, and probably never have.
Humans use 25% of the foliage on our planet for ourselves and our food. Yields are increasing, and there is room for growth in an age of crops and animals improved by science. In many respects things are improving. Fertility and population growth are declining. The ninth billionth person will be here by 2050 not by 2025 as an extrapolation of the figures once suggested. By 2075 population growth may have ceased.
But while there is hope for a better world, no one would defend the harsh statistics that show how far we must go to benefit humanity as a whole.
I imagine an alien spaceship arriving at our planet and its inhabitants asking to meet the world's representatives at the United Nations. How would we explain the state of our species, and our stewardship of our home planet, given our intelligence, resources and abilities when, for every 100 people on Earth;
20 possess 75% of the wealth.
50 suffer from malnutrition. 20 are starving. One is dying of starvation.
15 are overweight.
56 have no sanitation. 20 no clean water.
70 are unable to read.
20 live in fear of war or the aftermath of war.
As we told them our record would our shamefaced excuse to the aliens be that we are young and promising with a hopeful future. That may be so. We could tell them we, as a species, have done great things. But would we believe it? And will the eight billionth person, scheduled to arrive in 2029, see a different world?
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