Population bomb:the UN responds

摘要

Fred Pearce's view of the latest United Nations population projections misrepresents our results (Nature473,125; 2011). The causes of the differences between the 2008 and the 2010 revisions are more complex and varied than he conveys.The figures he cites to show that fertility estimates are lower than those made two years ago are the projected fertility figures for 2010-15 in the 2010 revision. The most recent estimates refer to 2005-10 and show an increase in fertility with respect to the 2008 revision in 84 countries, a decrease in 56 countries, and no change in the other 57 countries considered. Estimated fertility for 2005-10 is higher in the 2010 revision for both developed and least-developed countries.