In this final episode Dr Alice Roberts explores how our species, homo sapiens, developed our large brain; and asks why we are the only one of our kind left on the planet today?
The Rift Valley in Kenya is thought to be the crucible of human evolution, and here Alice examines the fossils in our family tree which reveal our brains have more than quadrupled in size since our ancestors split from chimpanzees. Drawing on research on social politics in chimpanzees, the cognitive development of children and the tools that have been found littered across the Rift Valley, Alice explores how and why our ancestors' brains became so big.
But our big brains came at a cost. Alice visits a maternity hospital to explore how our difficulties in giving birth are a result of our large-brained babies, and travels to meet the women of the Hadza tribe to explore how looking after our large-brained children has shaped the life histories of all of us.
Successive species of increasingly large-brained humans migrated around the world - from homo erectus to heidelbergensis, the Neanderthals to us. It's always been assumed the reason that homo sapiens succeeded where others failed is to do with our large brains. But comparing skulls it's clear Neanderthals had just as big a brain as us. So why is there only us left? Alice goes to meet Svante Paabo, decoding the Neanderthal and human genome, and Clive Finlayson, who is unearthing the Neanderthals' final settlement, to try to find out...
PRODUCTION DETAILS:
Presenter: Alice Roberts (Digging for Britain, Don't Die Young). Executive Producer: Sacha Baveystock (Global Warming: What We Need to Know). A BBC Production. |
