Adam Rutherford explores new insights into what lies at the very centre of the Earth. New research from China and the US suggests that the innermost core of our planet, far from being a homogenous iron structure has another, distinct region at its centre. He talks to the study's lead researcher Xiangdong Song and to geophysicist Simon Redfern about what this inner-inner core could tell us about the very long history of the Earth and the long suspected swings in the earth's magnetic field.

Professor Andrea Sella, from University College London is a recipient of the Royal Society's Michael Faraday Prize, in recognition, like Faraday himself, of exemplary science communication to the lay public. Andrea gave his prize lecture this week, describing chemistry as one of the 'crowning intellectual achievements of our age'. How justified is the claim? What have chemists ever done for us?

The sea forms the basis of ecosystems and industries, and so even subtle changes to the waters could have serious knock on effects. Dr Susan Fitzer from the University of Glasgow has been wading into Scottish lochs to study shelled creatures; they form a vital basis for marine ecosystems and the global food industry. But what effects could ocean acidification have on this vital organism?

And to mark Darwin Day Adam Rutherford examines the origins of Creationism and its most recent variation Intelligent Design. Why do opinion polls in the US routinely find that about half of the population denies the truth of Darwin's theory and believes instead that humans were created supernaturally by God at some point within the last few thousand years? He hears from historian Thomas Dixon, and from Eugenie Scott, former director of the National Centre for Science Education - a US organisation committed to keeping evolution (and now climate change) in the US schools' curriculum.

Producer: Adrian Washbourne.