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
Pangean megamonsoon solar insolation shifted toward the Southern Hemisphere. Air then traveled from Laurasia (region of high pressure), across the Tethys Ocean to Gondwana (region of low pressure). Moisture advection toward the Southern Hemisphere would have fueled heavy precipitation along the Gondwana coasts, while Laurasia remained very dry. There are marked similarities between factors contributing to the East Asian monsoon and those that would have influenced Pangean climate. This not only supports the theory that Pangean climate was dominated by the monsoon, but also aids in the study of it, providing paleoclimatologists with a present-day example to which they can compare their