Watch Walking With Beasts

It is 30,000 years ago and Earth is in the middle of an ice age. The landscape is dominated by the mighty mammoths, living side by side with woolly rhinos, giant deer and 2 separate species of human.

One million years ago, South America was home to a wealth of exotic oversized creatures found nowhere else on Earth.

A group of ape-like Australopithecus sit transfixed and stunned by the death of one of their members. The eldest female has fallen victim to malaria.

For well over 40 million years forests have dominated the world. They have been the cradle of evolution for the mammals, but the world is changing.

The mass extinction event that saw the demise of the dinosaurs and more than 70% of known land animals was almost as devastating in the seas.

For 160 million years the dinosaurs have ruled the world, while mammals have lived in their shadow - small animals clinging to safety in burrows in the ground and nests in the trees above. But the planet and its inhabitants have started to sicken, until the final straw comes - a ten kilometre wide meteor crashes into the Earth wiping out the dinosaurs and almost half of all known animals.