“Spirits of the Ice Forest” quotes from Walking with Dinosaurs

Dawn, over a silent forest a few hundred miles from the South Pole. It is the end of months of total darkness, and as the sun's rays filter down through the trees, they reveal a cold, harsh world. Here there are polar dinosaurs, adapted to cope with extreme conditions. But even they struggle to stay alive.

It is the mid-Cretaceous period, and dinosaurs are now more widespread than ever, reaching every part of the globe. But one place is a special challenge: the South Pole. Here, a giant continent made up of South America, Australia and Antarctica is kept warm by ocean currents that are forced down from the equator to encircle it. Instead of ice caps, there are lush forests. But unlike the unchanging tropical climate elsewhere, Antarctica has seasons, from hot summers under midnight sun to cold winters of total darkness.

Leaellynasaura is a dinosaur that is adapted to this extreme climate. Throughout the winter they survive in the warm sheltered heart of the thick forest. But now in spring they emerge to feed on the fresh plant growth. They are just two meters long and their most distinctive feature is their large eyes, which help them find food in the dark winter.

[about the Koolasuchus] This bizarre looking creature is a relic from a time before dinosaurs. In most parts of the world, competition from crocodiles has driven these magnificent amphibians to extinction. But here the waters get too cold for crocodiles, and the world's last Koolasuchus survive, still patrolling the waterways, just as their ancestors did 150 million years before them.

The polar allosaur is a smaller descendant of the great carnivores of the Jurassic, 50 million years before. His type are rare in the Cretaceous, but they survive here at the South Pole.

The giant carnivore has killed the dominant female. It is a bitter blow. Winter is coming, and without a lead female there will be tension in the clan.

Life on the Poles is a remarkable evolutionary achievement for the dinosaurs. But eventually, a slight cooling in the world's climates will spell doom to these lush Antarctic forests. And without them, all these unique dinosaurs will also disappear.

Away from the Poles, the dinosaurs continued to thrive for another 40 million years before extinction. In the final program, we will see how just before the end of their reign, they evolved the most terrifying predator that has ever walked the Earth.