The new head of the Science Museum has an uncompromising view about how global warming should be dealt with: get rid of a few billion people. Chris Rapley, who takes up his post on September 1, is not afraid of offending. 'I am not advocating genocide,' said Rapley. 'What I am saying is that if we invest in ways to reduce the birthrate - by improving contraception, education and healthcare - we will stop the world's population reaching its current estimated limit of between eight and 10 billion. That in turn will mean less carbon dioxide is being pumped into...