Paul Ehrlich still believes that overpopulation imperils the Earth’s
future. But the good news is we are approaching a demographic turning
point: Birth rates have been falling dramatically, and population is expected to peak later this century — after that, for the first time in modern history, the world's population
should actually start to decline.

With soaring prices for agricultural goods and new demand for biofuels, the clearing of the world's largest rain forest has accelerated dramatically. Unless forceful measures are taken, half of the Brazilian Amazon could be cut, burned or dried out within 20 years.

By taking bits of a single gene, scientists are using DNA barcoding to identify new species. If a portable hand-held scanning device can be developed, one ecologist says, it could “do for biodiversity what the printing press did for literacy.”

When it comes to setting climate change policy, science can only tell us so much. Ultimately, a lead report author for the Intergovernmental Panel on Climate Change writes, it comes down to making judgments about what is fair, equitable, and just.