Moving on to Ethiopia 3.2 million years ago, we witness the beginnings of mankind via a group of australopithecus - a type of ape which, like us, walks upright on two legs. But unlike us, these early members of the human family weren't predators, they were prey. Things get worse for the group as they are hunted by a sabre-tooth cat called dinofelis and fall victim to other dangers such as malaria, rival australopithecus and a rampaging 14-tonne deinotherium.
Back one million years ago, South America was a continent of exotic oversized creatures found nowhere else on Earth - huge terror birds, giant ground sloths and spiky-tailed relatives of the armadillo as big as cars. The deadliest animal of them all was smilodon, the largest of the sabre-tooth cats, with canines like carving knives. The programme follows the fortunes of an individual male, Half Tooth. Ousted from his clan by a pair of rival males, his life suddenly becomes a struggle to survive in this alien world.
Travelling forward in time to 30,000 years ago, it's the middle of an ice age. The landscape is dominated by mighty mammoths, living side-by-side with woolly rhinos, giant deer and two separate species of human. The programme follows the fate of a herd of mammoths in their annual struggle against the harsh ice-age conditions. Every summer they spend on the grassy plains of what will one day become the bottom of the North Sea, but every winter they are forced to head for the less exposed valleys further south. It is a journey fraught with danger: mammoths can get trapped in frozen bogs, and the herd must run the gauntlet of hunters like cave lions and the deadly Neanderthals.
