An outbreak of pathogenic bird flu, H5N1, in a Spanish mink farm could be a cause for concern. Some experts fear the virus may now spill over to other mammals without strict surveillance. Marion Koopmans, professor of virology at Erasmus Medical Centre, talks Roland through the potential risks. India’s caste system affects all aspects of society, but how does the hierarchy influence representation of marginalised groups in academia? Science journalist Ankur Paliwal believes that, despite efforts to combat discrimination, not enough is being done, and he has the data to prove it. Imagine a robot... Is it hard, metallic and humanoid? Professor Carmel Majidi from Carnegie Mellon University and his colleagues are thinking outside the robotics box. Their new material, magnetic in nature, can shift between solid and liquid states. It’s even capable of breaking out of robotic jail... From Lawrence of Arabia to Star Wars via tales of intrepid adventurers traversing lonely sandswept landscapes, deserts have always had a powerful pull on the popular imagination. But if a desert is full of sand, where did all that sand come from in the first place? That’s what CrowdScience listener Andy wants to know, so presenter Caroline Steel heads off into the dunes to try and find out. Along the way she’ll be wondering what a desert is anyway and whether it’s always sandy, as well as tracing the flow of material across the huge, ever-shifting sand seas of the Sahara. From deserts fed by sand from mountains thousands of kilometres away, to dunes migrating across the entire continent of Africa, we’ll discover how sand has just the right properties to be carried along by the wind. We’ll also explore how the sand in every desert has a unique fingerprint, and find out how fish bones in the Sahara tell the story of its lush, green past. Image credit: Ole Jensen/Getty