David Attenborough is in the Swiss Jura Mountains to discover the secrets of a giant. Beneath his feet lies a vast network of tunnels and chambers, home to a huge empire of ants. It is believed to be one of the largest animal societies in the world, where over a billion ants from rival colonies live in peace. Their harmonious existence breaks many of the rules for both ants and evolution, and raises some important questions. Through winter, spring and into summer, David turns detective to find the answers.
What can the struggles of sturgeons and muskrats, two key Great Lakes species, tell us about the impact of upstream dams on the local ecosystem? Join conservationists as they assess the threats to the habitats of these animals and weigh options to counteract the damage before it's too late.
Can animals count? This is a question that has intrigued and fooled investigators for a long time. Just over 100 years ago, a German horse called Hans was declared a mathematical genius but all was not as it seemed. And strangely, some bamboos around the world flower exactly at the same no matter where they are. Are they counting down the years?
Cameras follow Japanese macaques in the snow-covered mountains of Japan, as they gather at steaming hot thermal pools to bathe and socialise. Elsewhere in the cool mountains of Mexico, cameras capture a spectacular gathering of billions of monarch butterflies, and in Bavaria, Germany, Spy Beaver gains unique access to the secretive world of the beaver.