Science commentator Allan Blackman joins Kathryn to talk about how smart watches could identify Parkinson's disease up to seven years before tell-tale symptoms appear. Electrons are round! How round? Very round! Allan will talk about why the discovery of their exactness matters. And did you know most common painkillers use chemicals from crude oil products? Researchers in the UK have managed to make them from pine trees instead. Allan Blackman is a Professor of Chemistry, School of Science, Auckland University of Technology.