420 million years
or 102 meters before today
Geological era: Paleozoic / Silurian
At the beginning of the Silurian, vertebrates develop movable jaws that allow them to grasp, hold and chop food. This opens up completely new feeding possibilities for the jawed animals. Bone scales form teeth that can sit on the edges of the jaws, in the oral cavity or in the gullet. This development is so successful that today there are only two jawless vertebrate groups (lampreys and hagfish).
After the end of the Ice Age at the beginning of the Silurian, a warm temperate climate prevails with a global average temperature of about 17 °C. For the first time, the oxygen concentration rises to 14 %, while the carbon dioxide concentration drops below 0.4 %. The continent Euramerica (Laurussia) is formed from the land masses Laurentia and Baltica.