During an excavation, a group of researchers of the Pisa University found a fossil dating back to 5 millions of years ago near Grosseto, in Tuscany. Probably, their studies can proves that the narwhals’ and the beluga whales’ ancestors could have lived in the tropical waters of the Mediterranean Sea: narwhals and beluga whales, usually defined as “the sirs of ice”, live in icy water and they never get away from it, so it is impossible to find them in warm waters. More precisely, in Arcille, near Grosseto, the experts found a fossil skull in a sand quarry, calling it “Casatia Thermophila”. The experts will do more researches on this area, because it is rich of organisms and fossils of the past years and a good analysis could led to important knowledge about their evolution. Now, visitors will be able to see the Casatia Thermophila in the Cetaceous Gallery in the Historical National Museum of Pisa, in Tuscany.