Takes us into the world of digestion and its amazingly complex environment.Our health, body shape, mood and even our evolution are determined by the unseen life forms that swarm throughout our bodies. There are worms in your bowels, bacteria in your mouth, fungi in your lungs and even viruses in your DNA.The combined genetic information of all these bugs is more than 150 times greater than our own genes. Their cells outnumber our own by 10 to 1. This collective menagerie is called the microbiome, and in a very real sense, it is the making of us all.
This episode is a pioneering exploration of the latest discoveries concerning the Amazon - by far the greatest river on Earth. It is the river of superlatives, flowing more than 4,000 miles from the Andes to the Atlantic. Its 1,100 tributaries drain the greatest river basin on the planet and along its incredible journey it collects and transports one-fifth of the world's fresh water. Due to its enormous size, it still hides secrets.