3/3 Pedalling through the heat and rain, John takes on a gruelling military fitness test. (R)
BBC One Northern Ireland, Northern Ireland HD only
High definition Audio described
BBC One Scotland, Scotland HD only
Chris Beardshaw delves into the micro-world of soil to reveal what it is and how it works. (R)
Amnesty International's online tool to help validate videos showing human rights abuses
BBC World Service
A deadly threat to horses or a vital moth habitat? A new survey maps the ragwort plant.
BBC Radio 4
Michaela Strachan presents the story and sound of the rock pipit. (R)
8/10 The team come face-to-face with the threats that the amazing Madagascan reef is facing. (R)
Cyfle i glywed rhai o bigion 'Galwad Cynnar' eto.
BBC Radio Cymru
Historical patterns from preserved plants.
Elevators: A cultural history. Also, Indian militants who embrace electoral politics.
3/14 Among the yachts of a millionaires' marina, a sea otter mum teaches her pup to survive. (R)
3/4 Iolo dives with friendly Atlantic greys seals off the Pembrokeshire coast. (R)
BBC Two Wales only
2/2 The team explores how the atmosphere changes with altitude.
Using stunning aerial footage, this film reveals the beauty and fragility of our planet.
2/2 Is mining the deep ocean the solution to the world's growing demand for valuable metals?
12/12 Physicist Dr Helen Czerski and meteorologist John Hammond make sense of Britain's weather. (R)
BBC Two except Scotland
4/6 Breathtaking scenic views and salmon angling on the west coast. (R)
BBC Two Scotland only
2/4 Donal MacIntyre learns about floods and the world's wettest places. (R)