How can an ascent to the top of Everest help to save lives in intensive care? This week we're exploring physiology at the extremes: altitude, depth and cold. How does the human body adapt and cope under these conditions? Also, news of improved gene therapy techniques for sight-loss disorders, when do babies become sympathetic, how to cloak your cat (or goldfish), and have scientists discovered the remains of the Tunguska meteorite that smashed into Siberia in 1908? Like this podcast? Please help us by supporting the Naked Scientists)