To reveal Eurasia's origins, Prof Iain Stewart climbs up to the "eternal flames" of Mount Chimaera and explains that where the South of Eurasia is today, there was once a ninety-million-square-kilometre Ocean known as the Tethys. Destruction of the Tethys Ocean led to Eurasia's formation. The freshwater fish called Karimeen, from the backwaters of Kerala in Southern India is a clue that India was once four thousand kilometres south of its current position on the other side of the Tethys, joined to Madagascar.