Across the world we are seeing the emergence of bacteria that have gone rogue. These are the superbugs, dangerous bacteria that are becoming resistant to our only defence: antibiotics. Horizon meets the scientists who are tracking the spread of these potential killers around the globe, and discovers the new techniques researchers are developing to help defeat these superbugs.
Isolated since the time of the dinosaurs, New Zealand's wildlife has been left to its own devices, with surprising consequences. Its ancient forests are still stalked by predators from the Jurassic era. It's also one of the most geologically active countries on earth. From Kiwis with their giant eggs, to forest-dwelling penguins and helicopter-riding sheep dogs, meet the astonishing creatures and resilient people who must rise to the challenges of their beautiful, dramatic and demanding home.
In this final episode, Iolo explores bird design - from their ability to fly to the way that their beak design, colour and camouflage enable them to live in the many habitats Wales has to offer. Using ultra-slow motion photography, Iolo looks at how garden birds have such control over take off and landing, and explains why fulmars are one of our most supreme fliers.
For many people Sardinia is THE Mediterranean dream island: picturesque coastlines are a reality here. The breathtaking underwater world is concealed beneath the crystal-clear water surrounding the island. Then on to Abruzzo, the same latitude as Rome, the wild heart of southern Italy.
Steve Backshall reveals the incredible influence that insects and their close relatives have on Earth's many ecosystems. In the grasslands of South America the landscape has been created almost solely by one team of insects - grass-cutter ants. Across the world's oceans one tiny creature plays such a key role that, without it, the largest animal on our planet, the blue whale, could not exist. And in East Africa the savannah would quickly be swamped in dung were it not for the activities of a certain beetle. Yet the greatest influence of all comes from a group of insects that have ultimately changed the colour and diversity of our planet.