Environment - current issues:
large areas subject to overpopulation, industrial disasters, pollution (air, water, acid rain, toxic substances), loss of vegetation (overgrazing, deforestation, desertification), loss of wildlife, soil degradation, soil depletion, erosion; global warming becoming a greater concern
Geography - note:
the world is now thought to be about 4.55 billion years old, just about one-third of the 13.7-billion-year age estimated for the universe
People ::World
Population:
6,790,062,216 (July 2009 est.)
Age structure:
0-14 years: 27.2% (male 950,127,898/female 894,359,186)
15-64 years: 65.2% (male 2,235,114,476/female 2,192,071,874)