More than 200 million years ago, Earth looked very different from the way it does today. Instead of separate continents, nearly all of the land on the planet was joined together into a single enormous landmass called Pangaea. This supercontinent was surrounded by a global ocean known as Panthalassa, which covered most of Earth’s surface. Pangaea existed during the late Permian and early Triassic periods, a time when life on Earth was undergoing dramatic changes.
Over millions of years, powerful forces deep within the planet slowly began to pull Pangaea apart. This gradual breakup started around 230 million years ago and continued at a pace far too slow for any single generation to notice. As the landmass split and drifted, it eventually formed the continents we recognize today, along with the oceans that separate them.
The concept of Pangaea was first proposed in the early 1900s by German scientist Alfred Wegener. He suggested that continents were not fixed in place but instead moved over time—a bold idea known as continental drift. At the time, many scientists were skeptical because Wegener could not explain what forces might cause entire continents to move.
That explanation arrived decades later, in the 1960s, with the development of the theory of plate tectonics. Scientists discovered that Earth’s outer layer is divided into large, rigid plates that slowly shift atop a hotter, softer layer beneath them. These moving plates can collide, pull apart, or slide past one another, reshaping the planet’s surface and carrying continents along for the ride.
What kind of life existed on Earth at that time?
At the time when Pangaea existed—during the late Permian and early Triassic periods—Earth was home to a wide range of living things, though they were very different from most life today.
On land, plants were already well established. Vast forests covered parts of the supercontinent, made up mainly of ferns, seed ferns, conifers, and ginkgo-like trees. Grasses and flowering plants had not yet evolved, so landscapes looked more rugged and sparse compared to modern forests.
Animals on land were dominated by reptiles and reptile-like creatures called synapsids, some of which were early relatives of mammals. These included animals like Dimetrodon, famous for its sail-shaped back (often mistaken for a dinosaur, though it lived long before dinosaurs appeared). Large amphibians were also common, especially near rivers and wetlands.
In the oceans, life was abundant and diverse. Seas were filled with trilobites (early arthropods), brachiopods, corals, ammonoids, and many types of fish, including early sharks. Marine ecosystems were complex and thriving, supported by microscopic organisms such as algae and plankton that formed the base of the food web.
Insects were also widespread on land and in the air. Giant dragonfly-like insects and early beetles lived during this time, benefiting from higher oxygen levels in the atmosphere than we have today.
It’s important to note that dinosaurs had not yet risen to dominance during most of Pangaea’s existence. They appeared later, during the Triassic period, after a massive extinction event at the end of the Permian—the largest mass extinction in Earth’s history—which wiped out most marine species and many land animals.
Today, there is strong evidence supporting the existence of Pangaea. Identical fossils have been found on continents now separated by oceans, suggesting those lands were once connected. Matching rock layers and mountain ranges appear on different continents, lining up like pieces of a jigsaw puzzle. Even the distribution of ancient plants and animals points to a shared geological past.
Pangaea remains a cornerstone of modern geology, helping scientists understand how Earth’s surface has changed over deep time—and reminding us that the planet we live on is constantly, if slowly, in motion.
Pangaea Map: By Scotese, Christopher R.; Vérard, Christian; Burgener, Landon; Elling, Reece P.; Kocsis, Ádám T. - "Phanerozoic-scope supplementary material to "The Cretaceous World: Plate Tectonics, Paleogeography, and Paleoclimate (doi:10.1144/sp544-2024-28)" from the PALEOMAP project". doi:10.5281/zenodo.10659112 https://zenodo.org/records/10659112, CC BY 4.0, Link
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