Shared Planet explores the link between a growing human population and wildlife and there is no other part of the natural world that is under as much pressure as the earth's soils. We rely on them to grow healthy crops, which they can only do if they support an appropriate community of bacterial, fungal and invertebrate life. Wildlife too depends on this diverse life that thrives in the soil, everything from birds to plants to insects. The earth worm is the surprising champion of soils and an animal that looks vulnerable in the face of human population pressure. Monty Don will be in the studio speaking with soil scientist Dr Helaina Black and soil biophysisist Professor Wilfred Otten.