the final episode deals with plants that live in hostile environments. Attenborough visits Ellesmere Island, north of the Arctic Circle, to demonstrate that even in a place that is unconducive to life, it can be found. Algae and lichens grow in or on rock, and during summer, when the ice melts, flowers are much more apparent. However, they must remain close to the ground to stay out of the chilling wind. In the Tasmanian mountains, plants conserve heat by growing into 'cushions' that act as solar panels, with as many as a million individual shoots grouped together as one. Others, such as the lobelia in Mount Kenya, have a 'fur coat' of dense hairs on their leaves. The saguaro cactus in the Sonoran Desert flourishes because of its ability to retain vast amounts of water, which can't be lost through leaves because it has none. Many desert dwellers benefit from an accelerated life cycle, blooming rapidly within weeks after rainfall. Conversely, Mount Roraima is one of the wettest places on Earth. It is a huge sandstone plateau with high waterfalls and nutrients are continuously washed away, so plants have to adapt their diet if they are to survive. A bladderwort is shown invading a bromeliad. Inhabitants of lakes have other problems to contend with: those that dominate the surface will proliferate, and the Amazon water lily provides an apt illustration. Attenborough ends the series with an entreaty for the conservation of plant species.

The fifth episode of the series is a fascinating exploration of the dinosaur era and its impact on the evolution of life on Earth. Through a journey of 200 million years, we discover how the breakup of Pangea and tectonic changes shaped biodiversity and created environments for dinosaurs and other forms of life to flourish. From the majestic Diplodocus to the formidable Allosaurus, the documentary brings to life the giants that once dominated our planet. Additionally, it shows the evolution of plants, highlighting the emergence of flowers and their symbiotic relationship with insects, such as termites and ants, whose social and evolutionary dynamics are explored in depth. The narrative also addresses the rise of mammals and their coexistence with dinosaurs, highlighting species such as the Numbat and their struggle for survival.
With stunning imagery and a captivating narrative, this episode is an invitation to learn, marvel, and reflect on the extraordinary history of life on Earth.