Birth rate reduction 'best way' to save planet

The 2 million Australians who organizers said joined in March's Earth Hour were disappointed that turning off the lights for 60 minutes only saved the equivalent of one person's carbon output for one year.

They shouldn't have been so surprised: among big countries, only the United States pumps out more carbon per capita.

A better way of trying to save the planet, argues University of Western Australia researcher Barry Walters, would be to switch the focus from limiting consumption to practising contraception.