British Geological Survey scientists have completed the first full geological survey of Lake Windermere in the English Lake District since the Royal Navy made a survey in the 1930s. Among other things, the survey will help researchers understand how quickly the ice retreated after the last Ice Age, how the lake evolved and which parts the Arctic Charr prefers to live in. Richard Hollingham went to visit scientists on the BGS's research boat the White Ribbon on the lake to talk to the scientists involved. Next up, Richard speaks to a dinosaur expert at London's Natural History Museum who is studying how and why some dinosaurs went from walking on two legs to four. It turns out that despite the popular 3D animations on the telly, we know very little indeed about how they walked.