In this final episode, Mary Beard delves even deeper into ordinary Roman life by going behind the closed doors of their homes. She meets an extraordinary cast of characters - drunken housewives, teenage brides, bullied children and runaway slaves - and paints a more dynamic, lusty picture of Roman family life. Mary uncovers their preserved beds, furniture and cradles, tries on Roman wedding rings and meets some eccentric wives like Glyconis, praised by her husband for liking a drink or two, and Allia Potestas, who lived in a Roman menage a trois. Mary explores Roman parenting, childbirth and children, including Sulpicius Maximus, an 11-year-old schoolboy who was worked to death by his pushy parents, and Geminia Mater, a 5-year-old tomboy. Finally, Mary paints a more nuanced picture of Roman slavery and asks why if it was such a brutal institution did many Romans choose to be buried with their servants - living cheek by jowl in death, as in life

Few sounds are more beautiful or moving than the underwater songs of the humpback whale. Male whales compete with their songs, which often last for 10 minutes at a time, and can be repeated for hours on end. Whales separated by thousands of miles of sea will sing almost identical songs. Researchers have found that the songs change throughout the breeding months, following a mysterious pattern repeated across the waves. Whales also use sound to hunt. To catch herring, humpback whales release a stream of bubbles to form a shimmering, circular fishing net. Emitting a repetitive loud scream, they scare the fish into a tight ball, then lunge out of the water to swallow the shoal whole. Now it seems that the long-held image of the gentle giant must change to one of a ferocious and opportunistic hunter.

The rainforest is home to more species of plants and animals than any other habitat on the planet. But for humans, life there is not as easy as it looks. Life in the trees requires great skill, ingenuity and sheer bravery. The Matis of Brazil carve 4-metre-long blow-pipes to hunt monkeys - in near total silence. Deep in the Congo forests, Tete defies death by scaling a giant tree using nothing more than a liana vine, and he must then negotiate an angry swarm of bees - all to collect honey for his family. Three children from Venezuela's Piaroa tribe venture deep into the jungle to hunt tarantulas - to toast for lunch! In West Papua the Korowai tribe show-off their engineering skills by building a high-rise home 35 metres up in the tree tops. Most memorable of all, in Brazil we join a unique monitoring flight in search an un-contacted tribe...