Canadian journalist John Ibbitson and political scientist Darrell Bricker have been receiving a lot of media attention for their book Empty Planet, which challenges the UN’s population projections for this century. The UN’s median projection has the world’s population reaching 9.8 billion by 2050 and 11.2 billion by 2100, while Ibbitson and Bricker predict it will peak at 9 billion by 2050 and then decline. The world will face the challenge not of too many, but of too few, people.

Most of the population increase in the UN’s projection results from growth in sub-Saharan Africa, where birthrates have not fallen as rapidly as anticipated. With some few exceptions, most other countries either have total fertility rates (TFRs) at or below replacement (2.1 children per woman) or are rapidly approaching that level.

Ibbitson and Bricker argue that the assumptions underlying the UN’s projections are wrong, and that rapid urbanization, along with better education, more empowerment for women, and increasing access to information will lead to smaller families. The slow decline in African birthrates results from a lack of investment in education during the 1980s and 1990s, such that women born in 1980 might have had less education than their mothers. With more spending on education and increasing female literacy, birthrates will go down. Ibbitson and Bricker say that some demographers, such as Wolfgang Lutz in Vienna, have been questioning the UN numbers for years but have been talking to one another through scholarly channels and not getting their ideas to the public.

It would be good news indeed if Ibbitson and Bricker are correct. And it is true that literacy rates, especially female literacy rates, have been going up and increased female education is correlated with decreasing fertility. However, it’s also true that fertility declines have stalled in many sub-Saharan African countries, that the desired family size often remains high even when birth control is available, that cultural norms are often still pronatalist, and that myths about the harms of contraceptives persist. Even if fertility rates fall substantially in the near future, the youthful age structure of the African population makes it likely that population growth will continue for some time.

What is very clear is that the Earth is currently undergoing an ecological crisis, with catastrophic declines in wildlife and insect populations. A substantial contraction of the human population through smaller families (rather than through starvation and war) would be a welcome development. But it would be unwise to assume that the problem of overpopulation will take care of itself. PIC will continue to promote smaller families and to campaign for universal access to family planning. A planet with a smaller human population, in which terrestrial and aquatic ecosystems have a chance to recover, will not be an “Empty Planet” but a far richer and more bountiful planet.