NOVA: Australia's First 4 Billion Years

Hidden in the red hills of Australia are clues to the mysteries of Earth's birth, how life arose and how it transformed the planet into the world we now live in. Experts unveil the earliest forms of life: an odd assortment of bacterial slime. Life like this would flood the atmosphere with oxygen and spark the biological revolution that conquered the planet. Travel with NOVA and host Dr. Richard Smith to meet the cast in the first scenes of the great drama of life on earth.

How did life storm the beaches and dominate planet Earth? Ancient Australian fossils offer clues. While the oceans were teeming, the world above the waves remained an almost lifeless wasteland — until the Silurian period, when the conquest of the land began. Host Richard Smith introduces Earth's forgotten pioneers: the scuttling arthropod armies that invaded the shores and the waves of green revolutionaries whose battle for the light pushed plant life across the face of a barren continent. Join NOVA's prehistoric adventure as four-legged animals walk onto dry land, with the planet poised for disaster.

Host Richard Smith comes face-to-face with the previously unknown reptilian rulers of prehistoric Australia. NOVA resurrects the giants that stalked the land and discovers that some of them were among the largest ever to have walked the Earth. Others were some of the most dangerous. In the dry desert heart, scientists unearth an ancient inland ocean, full of sea monsters. But reptiles didn't have the world all to themselves. Mammals like the enigmatic platypus lived alongside them, ready for their day in the sun. And 65 million years ago, that day arrived.

After the asteroid impact 65 million years ago — believed to have wiped out the dinosaurs — Australia was set adrift on a lonely voyage in southern seas. With host Richard Smith at the wheel, NOVA travels this walkabout continent to uncover how it became the strange island it is today. Australia's many unusual creatures, like the kangaroo and the cassowary, tell a tale of isolation, change and resilience. Australia's long history has seen mountains rise and fall, seas come and go, and whole kingdoms of life triumph and disappear. In this final episode, NOVA races down the last 65 million years to the present day.