Gretchen Stevens and colleagues (Sept 1, p 824),1 in their study of progress towards Millennium Development Goal 1 (MDG 1), note that the probability of sub-Saharan Africa reaching it is “virtually zero”. This is because many African communities are demographically trapped2—ie, they are exceeding the carrying capacities of their ecosystems, with nowhere to go and with insufficient exports to exchange for food and other essentials. African populations have quadrupled since 1950, and are expected to more than double again by 2050.3 Most mothers still have more than five children; in Uganda, where the government is still pronatalist, they have an average of 6·2.4
Unfortunately, carrying capacity is not discussed in demography or development economics, since it is not supposed to apply to man, even in the villages of Africa. The possibility of its being exceeded is therefore not discussed either—the so-called Hardinian taboo.5 African communities—and especially some African governments—are in dire need of the crunch message, which is “reduce your fertility or starve”. Mercifully, this message is well taken by trapped communities in Africa, however politically incorrect it might be elsewhere. Africa will never reach MDG 1 without addressing it.