Dr Chris and Dr Xand learn about space. They find out all about the angle of the Earth's spin and how it affects lots of things, including the four seasons. Show more

Dr Chris and Dr Xand learn about space. They discover that the Earth has an invisible force field that protects it from deadly solar winds. Show more

Dr Chris and Dr Xand learn about space. In this episode they investigate one of the biggest questions in the universe - are there aliens out there? Show more

Dr Chris and Dr Xand meet animal experts around the world. They find out all about one of the biggest animals on earth - elephants. Show more

Dr Chris and Dr Xand meet the top animal experts on the planet. They find out all about the tallest animals on earth - giraffes. Show more

Doctors Chris and Xand van Tulleken meet the top animal experts on the planet. They find out about orangutans, and Clare Balding travels to Borneo. Show more

Dr Chris and Dr Xand meet animal experts around the world. They find out about dolphins and sharks and what makes them such amazing swimmers. Show more

Dr Chris and Dr Xand meet animal experts around the world. They find out all about gorillas when Clare Balding travels to West Africa to meet Shufai the gorilla. Show more

Dr Chris and Dr Xand meet animal experts around the world. They discover how animal dentists help two creatures with tricky teeth. Show more

Dr Chris and Dr Xand meet animal experts around the world. They learn about moon bears, and Steve Leonard visits a sanctuary for rare Asiatic bears. Show more

Dr Chris and Dr Xand meet animal experts around the world. They find out all about big reptiles, and animal expert Steve Leonard meets Martha the alligator. Show more

Dr Chris and Dr Xand meet animal experts around the world. They find out all about one of the biggest animals on the planet - rhinos. Show more

Dr Chris and Dr Xand meet animal experts around the world. They find out all about some furry and fishy creatures who are having a check-up. Show more

Dr Chris and Dr Xand return to Store Glacier in Greenland with a team of top experts and explorers to find out more about glaciers and icebergs. Show more

Dr Chris and Dr Xand explore an incredible but dangerous underground world of massive caves and tunnels within Store Glacier. Show more

Dr Chris and Dr Xand are in Greenland to learn about glaciers and icebergs. Chris begins an experiment to investigate the smallest inhabitants of the glacier - mosquitoes. Show more

Dr Chris and Dr Xand are in Greenland to learn about glaciers and icebergs. Chris Packham wants to investigate some icy whirlpools at Store Glacier. Show more

Dr Chris and Dr Xand are in Greenland to learn about glaciers and icebergs. The scientists brave the bears to place sensors to discover how wave movement affects the iceberg. Show more

Dr Chris and Dr Xand are in Greenland to learn about glaciers and icebergs. The scientists and explorers spend their last day at the iceberg. Show more

Dr Chris and Dr Xand are in Greenland to learn about glaciers and icebergs. They leave their camp and head out across the high Arctic seas. Show more