If you have ever wondered what would happen in your own home if you were taken away and everything inside was left to rot, the answer is revealed in this programme which explores the strange and surprising science of decay. For two months, a glass box containing a typical kitchen and garden was left to rot in full public view within Edinburgh Zoo. In this resulting documentary, Dr George McGavin and his team use time-lapse cameras and specialist photography to capture the extraordinary way in which moulds, microbes and insects are able to break down our everyday things and allow new life to emerge from old. Decay is something that many of us are repulsed by, but as the programme shows, it's a process that's vital in nature. And seen in close up, it has an unexpected and sometimes mesmerising beauty.
The episode begins in the South American rainforest whose rich variety of life forms is used to illustrate the sheer number of different species. Since many are dependent on others for food or means of reproduction, David Attenborough argues that they couldn't all have appeared at once. He sets out to discover which came first, and the reasons for such diversity. He starts by explaining the theories of Charles Darwin and the process of natural selection, using the giant tortoises of the Galapagos Islands (where Darwin voyaged on HMS Beagle) as an example. Fossils provide evidence of the earliest life, and Attenborough travels a vertical mile into the Grand Canyon in search of them.
David Attenborough highlights the curiosities that have led to accusations of forgery, but have ultimately helped assist the rethinking of evolution. When early explorers brought the first specimen of a duck-billed platypus to England in 1799, it was considered so bizarre it was deemed a hoax. Similarly, the midwife toad became the centre of a scientific storm in the 1920s that led to accusations of fakery.
Natural World visits the Arizona desert, where a new honey ant queen wages an intense battle for survival as she attempts to build and defend her empire. Eliminating rivals with ruthless efficiency, sacrificing thousands in her quest for domination, murder, cannibalism, genocide - she will do anything to keep her crown. Empire of the Ants is the epic story of one honey ant queen's dramatic rise to power - and her brutal fall from grace.