Separating the facts from fiction

MYTH ONE: the earth's population is spinning out of control. The UN forecasts that world population will rise from 5.6 billion to about 10 billion in 2050. So are we doomed? No. Many more people can be fed and sheltered; the rate of population increase has fallen from over 2 per cent in the 1960s to 1.7 per cent in the Eighties and Nineties. Many developing countries have made good progress in reducing their growth rates over a couple of decades.

MYTH TWO: the earth's 'carrying capacity' for humans has already been reached. Pessimists point out that the world's per capita production of cereal crops has faltered in the past few years after rising steadily for decades. This is probably a blip - people can grow more food to feed rising numbers, relying on agricultural improvements, new technologies and the clearance of land under forest.

MYTH THREE: overpopulation is the root cause of Third World poverty. True in some places where natural resources are overstretched, but there are other reasons for poverty: conflict, debt, lack of capital and education, and feudal systems of land holding. Where demography may add to poverty, it is important to sort out whether it is the rate of population growth or the absolute numbers which are the problem. Economic growth may struggle to keep up with a fast growing population.

MYTH FOUR: Catholic countries have high population growth rates. Some do, but Italy - from where the Pope condemns the Cairo conference - has the world's lowest fertility rate and its population is falling. Spain also now has a very low birth rate.

MYTH FIVE: there is no need to worry about population growth. Optimistic economists argue that the earth can support many, many times more people than live on it now. Human ingenuity and new technologies will continue to improve an expanding population's lot. Probably they are right, but there have to be some limits. The wildlife we share the planet with is fast dwindling and some of the most basic natural resources -fish, soil, fresh water - are manifestly over-exploited.