Plate tectonics Columbia or Nuna formed during a period of and broke up about . The supercontinent Rodinia is thought to have formed about 1 billion years ago and to have embodied most or all of Earth's continents, and broken up into eight continents around . The eight continents later re-assembled into another supercontinent called Pangaea; Pangaea broke up into Laurasia (which became North America and Eurasia) and Gondwana (which became the remaining continents). The Himalayas, the world's tallest mountain range, are assumed to have been formed by the collision of two major plates. Before uplift, they were covered by the Tethys
Saltoposuchus in newly found ecological niches, Pangaea started splitting into Laurasia and Gondwana, and the air was very arid with hot summers and cold winters. After marine life had been wiped out by the mass extinction event, the Triassic waters were populated with very few families of fish. The Triassic Period showed the first development of modern stony corals and a time of modest reef building activity in the shallower waters of the Tethys near the coasts of Pangaea. During the Mesozoic Era, early mammals, reptilian species, and other insects populated the land. Insects that had survived the mass extinction and