Alice travels to Africa in search of the birthplace of the first people. They were so few in number and so vulnerable that today they would probably be considered an endangered species. So what allowed them to survive at all?

In this programme, the journey continues into Asia, the world's greatest land mass, in a quest to discover how early hunter-gatherers managed to survive in one of the most inhospitable places on earth.

When our species first arrived in Europe, the peak of the Ice Age was approaching and the continent was already crawling with a rival.

Alice looks at our ancestors' seemingly impossible journey to Australia. Miraculously preserved footprints and very old human fossils buried in the outback suggest a mystery: that humans reached Australia almost before anywhere else.

For Stone Age people, reaching North and South America seems impossible - on each side vast oceans, and to the north an impenetrable ice sheet that covered the whole of Canada. So how did the first Americans get there?