Fred Pearce says there 's good news attached to the 7 billion population milestone . The UN estimates that by 2050, global average life expectancy will be around 80 years old and then drop gradually over time as people live longer lives in poorer countries. He says small families new norm as old reasons for having more children are gone . Pearce : Problem now is smaller population has upped its consumption , environmental damage .
Fred Pearce says there 's good news attached to the 7 billion population milestone . He says woman are having far fewer children than their forebears ; global average is 2.5 . He says small families new norm as old reasons for having more children are gone . Pearce : Problem now is smaller population has upped its consumption , environmental damage .