Soar over Namibia as we take you on a tour of an ancient world, from the oldest desert on Earth to the emerald green waters of the Kunene River. On the journey, we delve into the country's rich culture, reborn from the shadows of its past.
With crystal-clear waters, breathtaking marine life, and teeming biodiversity, the Caribbean island of Bonaire is a top destination for ecotourists. Visit one of the world's great ocean parks and see how the influx of travelers is fueling an ambitious project to conserve it.
In this final episode we complete our journey, travelling back from the March equinox to the end of June. Kate Humble is in the Arctic at a place where spring arrives with a bang, whilst Helen Czerski chases a tornado to show how the earth's angle of tilt creates the most extreme weather on earth.
It is high summer in the Polar Regions, and the sun never sets. Vast hordes of summer visitors cram a lifetime of drama into one long, magical day; they must feed, fight and rear their young in this brief window of plenty. Summer is a tough time for the polar bear family, as their ice world melts away and the cubs take their first swimming lesson. Some bears save energy by dozing on icy sun beds, while others go egg-collecting in an Arctic tern colony, braving bombardment by sharp beaks. There are even bigger battles on the tundra; a herd of musk oxen gallop to the rescue as a calf is caught in a life and death struggle with a pair of Arctic wolves. But summer also brings surprises, as a huge colony of 400,000 king penguins cope with an unlikely problem - heat. The adults go surfing, while the woolly-coated chicks take a cooling mud bath. Nearby, a bull fur seal is prepared to fight to the death with a rival. Fur flies as the little pups struggle desperately to keep out of the way of the duelling giants. Further south, a minke whale is hunted amongst the ice floes by a family of killer whales. The dramatic chase lasts over 2 hours and has never been filmed before. The killers harry the minke whale, taking it in turns to wear it down. Eventually it succumbs to the relentless battering. Finally, comical adelie penguins waddle back to their half a million strong colony like clockwork toys. The fluffy chicks need constant feeding and protection as piratical skuas patrol the skies. When an unguarded chick is snatched, a dramatic "dogfight" ensues.
Spring arrives in the polar regions, and the sun appears after an absence of five months; warmth and life return to these magical ice worlds - the greatest seasonal transformation on our planet is underway. Male Adelie penguins arrive in Antarctica to build their nests - it takes a good property to attract the best mates and the males will stop at nothing to better their rivals! But these early birds face the fiercest storms on the planet. In the Arctic, a polar bear mother is hunting with her cubs. Inland, the frozen rivers start to break up and billions of tons of ice are swept downstream in the greatest of polar spectacles. This melt-water fertilizes the Arctic Ocean, feeding vast shoals of Arctic cod and narwhal. The influx of freshwater accelerates the breakup of the sea-ice - an area of ice the size of Australia will soon vanish from the Arctic. On land, a woolly bear caterpillar emerges from the snow having spent the winter frozen solid. Caterpillars normally become moths within months of hatching, but life is so harsh here that the woolly bear takes 14 years to reach adulthood. Once mature it has only days to find a mate before it dies! Alongside the caterpillars white Arctic wolves race to raise their adorable cubs before the cold returns.
In the culmination of this 1,000km scientific expedition aboard the Alucia, Liz Bonnin and the team of scientific experts journey south to visit the oldest islands in the Galapagos to see first-hand the impact that humans have had on this pristine wilderness. Back on the larger island of Isabela, where her journey first began, Liz descends into a spectacular vertical lava cave. Deep inside, she discovers how this hidden world could even provide an answer to how it might be possible to inhabit other planets. On her last land-based stop, on Santa Cruz, Liz comes face to face with the effects of man as she explores the magical misty scalesia forests and meets scientists who are tracking the invasive species spreading throughout the islands. It is here that she also checks in on a giant tortoise population whose ancient migration pathways have come under threat from the largest human population on the archipelago, and meets a man on a mission to protect this iconic creature. Finally, Liz dives into the deep blue waters to witness the birth of a brand new island. Coming full circle, Liz and the team are able to reflect on the importance of their missions which will help to protect the Galapagos and its extraordinary wildlife in the future. In an ever-changing world, what we learn now from these incredible living natural wonders and what we can pass on to future generations has never been more important.