Professor Jim Al-Khalili looks at how we have created machines that can simulate, augment, and even outperform the human mind - and why we shouldn't let this spook us. He reveals the story of the pursuit of AI, the emergence of machine learning and the recent breakthroughs brought about by artificial neural networks. He shows how AI is not only changing our world but also challenging our very ideas of intelligence and consciousness.
Along the way, we'll investigate spam filters, meet a cutting-edge chatbot, look at why a few altered pixels makes a computer think it's looking at a trombone rather than a dog and talk to Demis Hassabis, who heads DeepMind and whose stated mission is to 'solve intelligence, and then use that to solve everything else'. Stephen Hawking remarked 'AI could be the biggest event in the history of our civilisation. Or the worst'. Jim argues that AI is a potent new tool that should enhance our lives, not replace us.

Dr Michael Mosley and Professor Alice Roberts investigate if male and female brains really are wired differently. New research suggests that the connections in men and women's brains follow different patterns, patterns which may explain typical forms of male and female behaviour. But are these patterns innate, or are they shaped by the world around us?" Using a team of human lab rats and a troop of barbary monkeys, Michael and Alice test the science and challenge old stereotypes. They ask whether this new scientific research will benefit both men and women - or whether it could drive the sexes even further apart.

Around the world, food allergies are surging to near-epidemic levels. Medicine is just beginning to understand why some people react to seemingly harmless foods. Scientists race to understand what's changed in our bodies, while farmers and chefs contend with new challenges.

The second episode looks at the challenges of hunting in the Arctic, the most seasonal place on Earth. To a predator, seasonal change is a problem. It means that all the parameters of the hunt - the conditions, the strategies, the prey - change too. The only option for the Arctic's top predators, the wolf, the Arctic fox and the polar bear, is to continually adapt to their changing world, exploiting the good times and enduring the bad.

Dr Alice Roberts 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. How could they have travelled so far from Africa, crossing the open sea on the way, and do it thousands of years before they made it to Europe? The evidence trail is faint and difficult to pick up, but Alice takes on the challenge. In India, new discoveries among the debris of a super volcano hint that our species started the journey much earlier than previously thought, while in Malaysia, genetics points to an ancient trail still detectable in the DNA of tribes today. Alice travels deep into the Asian rainforests in search of the first cavemen of Borneo and tests out a Stone Age raft to see whether sea travel would have been possible thousands of years ago, before coming to a powerful conclusion.

As man moves to colonize the cosmos, the realities of sexual relationships and reproduction need to be addressed. Probe the physiological, psychological and cultural challenges of sex in space.