The mass media have been discussing these findings with shock and alarm, because such information is likely to be new and surprising to anyone who has never gone through the all-consuming herculean effort of motherhood. To anyone who has, the idea that most women would choose to have two or fewer children if given the resources, information and freedom to do so is just self-evident common sense.
02 August 2001
There has been enormous concern about the consequences of human population growth for the environment and for social and economic development. But this growth is likely to come to an end in the foreseeable future. Improving on earlier methods of probabilistic forecasting1, here we show that there is around an 85 per cent chance that the world’s population will stop growing before the end of the century. There is a 60 per cent probability that the world’s population will not exceed 10 billion people before 2100, and around a 15 per cent probability that the world’s population at the end of the century will be lower than it is today.
This is projected to lead to a drop in the fertility rate of the world’s population, from an average of 2.37 children per woman — 237 children from every 100 women — to 1.66, or 166 children for every 100 women.
The fertility rate must be 2 for a population to remain stable and 2.1 for it to increase, the researchers said. To keep a community the same size a mother must, on average, not only replace herself but also the baby’s father.
Having fewer children is also undoubtedly positive from an environmental point of view; recent research has found that having one fewer child reduces a parent’s carbon footprint by 58 tonnes of CO2 a year.
Stanford biologist Paul Ehrlich wrote in his best-selling 1968 book The Population Bomb, “In the 1970’s, hundreds of millions of people will starve to death” because of overpopulation. (Later editions modified the sentence to read “In the 1980’s.”)
None of that ever came to pass.
Human overpopulation (or population overshoot) is when there are too many people for the environment to sustain (with food, drinkable water, breathable air, etc.). In more scientific terms, there is overshoot when the ecological footprint of a human population in a geographical area exceeds that place’s carrying capacity, damaging the environment faster than nature can repair it, potentially leading to an ecological and societal collapse. Overpopulation could apply to the population of a specific region, or to world population as a whole.