The team put more science to the test. Dallas looks at the origins of our weather and explains how the emergence of seasons allowed life to form, all with the help of a grenade launcher. Jem travels to Scotland to check out the latest green technology - wave power. And Liz meets Richard Dawkins to prove evolution. The programme is co-produced with the Open University. For more ways to put science to the test, go to www.bbc.co.uk/bang and follow the links to The Open University.