The first episode tells how invertebrates became the first creatures of any kind to colonise dry land. Their forerunners were shelled and segmented sea creatures that existed 400 million years ago. Some of them ventured out of the water to lay their eggs in safety, and Attenborough compares those first steps with today's mass spawning of horseshoe crabs off the Atlantic coast of North America.
2005 • Nature
The next programme deals with flying insects. It begins in Central Europe, where the Körös River plays host to millions of giant mayflies as they rise from their larval skins to mate. — the climax of their lives. Mayflies and dragonflies were among the first to take to the air about 320 million years ago, and fossils reveal that some were similar in size to a seagull. Damselflies are also looked at in detail.
2005 • Nature
The final programme looks at the superorganisms formed by bees, ants and termites. Attenborough reveals that their colonies, whose individuals were once considered purely servile, are "full of conflict, power struggles and mutinies." They evolved when such creatures moved away from a solitary existence and started building nests side-by-side, which led to a collective approach to caring for their young.
2005 • Nature
As almost all animal inhabitants of Antarctica are forced to migrate north, the sea underneath the frozen ice still provides a home to many specially adapted fish whose cells are protected from freezing through an "antifreeze" liquid. Many of them feed on the faeces of other animals. The most notable larger animal that does not migrate north is perhaps the Weddell Seal, which can be found as close as 1300 kilometres to the pole. Groups of seals tear holes into the ice to dive for food and come up to breathe. The females come back to the ice to give birth.
Snakes have developed the ultimate economy of design and are the most elegant and iconic of hunters. Among the incredible species seen here are blind tiger snakes that hunt using their sense of smell, magnificent African spitting cobras and a bizarre turtle-headed sea-snake hunting on a coral reef. And, for the first time ever, cameras capture a snake ambush in the wild and the beautiful spectacle of yellow anacondas giving birth underwater.
How can you tell the two poles apart? Where are the penguins? What about the bears? The Arctic pole is located in the Northern Hemisphere within the deep Arctic Ocean, while the Antarctic pole is smack in the middle of the ice-covered Antarctica. Camille Seaman describes how enterprising people and organisms have found ways to reside around both poles despite the frigid temperatures.
The American Dipper can plunge its head into freezing Arctic water up to 60 times a minute. In the summer, ferocious mosquitoes can draw up to a pint of blood a day from caribou. Take a fascinating look into the Arctic seasons and the impact that rising sea levels have on local wildlife, and, ultimately, our own world.