At least 5 times all life on earth has been on the verge of extinction. Some say that we are close to the sixth. In this episode the scientists take a closer look at the mass extinctions in our history. What did really happen 250 million years ago, when 95 percent of all sea-living species died out? Is there something we can learn, that we can use today, when the number of species on earth is dwindling and the eco systems are quickly changing?

Mars Peerless - the story about Erik XIV and the biggest warship in the world. It was a sensation in the marine archeology world when the fabled warship Mars Peerless (Makalös) was found at the bottom of the Baltic Sea in the summer of 2011, after nearly 450 years of fruitless searches. Mars was bigger than the Vasa ship and it was Erik´s big trump card to win dominion of the Baltic Sea. During three seasons the archeologists have thoroughly investigated the ship and in this autumn premiere of Vetenskapens värld we tell you about a brutal naval battle with a violent outcome. When Mars sank it took around 800 Swedish and German sailors with it to the bottom of the sea.