What Was Pangea?

Approximately 345 million years ago (mya) during the Devonian and Carboniferous ages of the Paleozoic era, before dinosaurs roamed, before birds and before mammals, geological forces were driving Gondwana (Gondwanaland), Euramerica, and Siberia — the Earth's three major landmasses — together to form the single supercontinent known as angea.

A Greek word meaning "all lands," it was a C-shaped continental jigsaw that stretched from the North Pole to the South Pole. The Panthalassa Ocean surrounded it, while its C-shape cradled the Tethys Sea. Pangea's creation pushed up the great Appalachian Mountains, the African Atlas Mountains, and the Russian Urals. It also heralded in two of the most awesome events in history: it bore witness to the largest mass extinction of life on Earth, and oversaw the birth and reign of the dinosaurs.

Insects and reptiles were still new to the world at the time the continent formed. Lands were covered with large primitive trees and ferns, and conifers or needle-leaved trees saw their first light. Eventually, 280 mya near the end of the Permian period, mammal-like reptiles walked the primitive lands. In the blink of a geological eye, however, Earth would nearly become devoid of life.

Many theories attempt to explain what happened at the end of the Permian and beginning of the Triassic period, 252 mya when 95% of all marine and terrestrial species went extinct. Known as the Great Dying, or more formerly, the Permian-Triassic extinction event, this global phenomenon has puzzled and intrigued scientists. Explanations range from supernovas to the volcanic creation of the Siberian Trapps.

Twenty-five million years later, the stage was set for perhaps the most awesome phase history has ever known: the Mesozoic era. From 248 - 65 mya, it encompassed three periods: the Triassic, Jurassic, and Cretaceous. Though the dynamics that brought Pangea together were already forcing it apart, the continent would endure long enough to witness yet another major event: The Age of the Reptiles.

The Triassic period not only saw the first turtles and mammals, but it gave birth to dinosaurs, which would come to rule the world for the next 150 million years. These earliest dinosaurs were hardy, small creatures, but in the Jurassic period that followed as the first birds took to the air, dinosaurs diversified and evolved into the huge beasts that still inspire awe and wonder.

As the supercontinent started to slowly open in the late Triassic and early Jurassic, 200 mya, waterways and low continental seas separated Gondwana and Laurasia like gigantic islands, then split the lands up further. In the final period of the Mesozoic era — the Cretaceous — the first flowering plants opened their petals as the first primates opened their eyes. By the end of this period, 65 mya, the continents were crawling towards their present-day positions, and the reign of the mighty dinosaurs came to a sudden end with the Cretaceous-Tertiary extinction event.

Though Pangea was not the first supercontinent, it was certainly the most interesting in terms of evolutionary life. A modern understanding of plate tectonics and other geophysical data has made it possible for scientists to reconstruct (and name) previous supercontinents. Rondinia, formed some 1 billion years ago, is thought to have broken up about 750 mya. Columbia is even older, at 1.5 - 1.8 billion years. Perhaps more interesting is the projection of Pangea Ultima by Dr. Christopher Scotese. If the predictions hold true, it is a mere 250 million years in our future.

Regardless of what the future holds, however, Pangea will likely stand alone as a land that saw the worst mass extinction in known history, the birth of modern life forms, and the reign of the dinosaurs.

German meteorologist Alfred Wegener, through his proposed theory of continental drift, first introduced the idea of this supercontinent in 1912. His theory was rejected, lacking a viable explanation for how landmasses could move, but the aspect of a single continent did fit scientific data. Only after Wegener's death in 1930 did new evidence arise that led to an understanding of plate tectonics and acceptance of his theory.