Gondwana is a huge supercontinent that was formed by smaller landmasses pushing together long before the Earth’s landmasses were inhabited by life. If you visit this former supercontinent, you can walk from South America to Antarctica, across Africa, and all the way to the east coast of Australia without ever going to sea. When the first dinosaurs walked the Earth, none of the continents we are familiar with existed in their present form. First Pangaea, then Gondwana, broke apart to form the continents of our world. Gondwana means land of the Gonds, the name of an Indian tribe and a region of India named after this tribe. To avoid confusion, the official name of the ancient supercontinent is Gondwanaland, but the nickname Gondwana is often used to refer to the ancient supercontinent where some of the first plants and animals lived and where the evolution of the first dinosaurs and the first marsupials was recorded. It existed for about 250 million years, both before and after the supercontinent Pangaea, and included all of present-day Australia, India, Antarctica, Zealandia, Africa, Madagascar, and South America. It was very vast.
Few people know about Gondwana’s role in Earth’s history, but many know about Pangaea, the last supercontinent. Many consider Pangaea to have been the first supercontinent, but it was only the latest in a 3 billion year lineage of supercontinents that formed when large parts of Earth’s continental crust converged into a single landmass. Before Pangaea formed, there were two other megacontinents: Gondwana and Laurasia/Euramerica. Euramerica was the confluence of most of the continents in the Northern Hemisphere, while Gondwana was the only major landmass in the Southern Hemisphere. The names of these past megacontinents don’t always agree (I like the name Euramerica best), nor do they agree on the exact definitions of the words supercontinent and megacontinent. A supercontinent is often defined as “a landmass made up of most or all of Earth’s landmass” (Encyclopedia Britannica), megacontinents are relatively small. A study The megacontinents were precursors to the formation of supercontinents, suggesting that Eurasia (Europe + Asia) is the only megacontinent we have today. In my humble opinion, the greatest of all the megacontinents is Gondwana, because it existed for a long time and provided a refuge for land life to survive and adapt in a turbulent world.
Starting about 800 million years ago, India, Madagascar, and East Africa collided, and by 530 million years ago, South America, Australia, Antarctica, and Africa joined the supercontinent Gondwana. Gondwana formed in the Southern Hemisphere, and was home to fossilized Ediacaran life forms in the Ediacaran Hills of Australia. Fossils of these ancient Gondwana life forms, ancestors of animals and plants, have also been found in Africa and South America.
Gondwana set the stage for and recorded the Cambrian explosion of marine life, the evolution of animals with skeletal features. In the shallow waters of the upper Gondwana shelf, the ancestors of modern cephalopods (squids and octopuses), cnidarians (jellyfish and corals), arthropods (insects and shrimp), and chordates (ancestors of fish) evolved. The oceans surrounding Gondwana later set the stage for the earliest fishes, the ancestors of all vertebrates, including us humans. Over the next few million years, the first fungi inhabited the land, followed by the first tropical land plants, land insects, trees, seeds, amphibians, and reptiles. The first widespread forests created soil and supported the Gondwana animals, but during the Carboniferous glacial period, most of Gondwana was buried under ice caps. Life flourished on land and in the sea. Gondwana then merged with Euramerica to form South Pangaea. As the supercontinent of Pangaea formed, a series of events occurred that pushed life to the brink of extinction. Huge mountain ranges formed as the Pangaean continents joined together, and remnants of these eroded mountains can be found in eastern North America (Appalachians), Scotland, Scandinavia, and Africa. The length of the world’s coastlines decreased, and vast deserts formed as forests disappeared. North Pangaea saw the largest recorded volcanic eruption in about 100,000 years. This ushered in the Great Dying, the largest extinction in the past 500 million years. Only 5-10% of the population survived, and only the best survivors adapted to the extreme world of Pangaea.
Conifers, cycads, and seed ferns were able to survive the Great Extinction because they were able to conserve water. Also, when conditions became unviable, their seeds could wait in the soil until conditions were good enough to germinate. Reptiles had scales to prevent dehydration and could lay their eggs on land. These characteristics allowed them to survive the desertification of Pangaea. Thus, the reptile survivors evolved into dinosaurs, crocodiles, pterosaurs, mammals, and birds. The organisms that inherited Earth could spread far and wide, limited only by sufficient food sources, deserts, and mountains, because the oceans did not prevent them from crossing the vast landmasses.
Fossil evidence indicates that the first dinosaurs evolved on the Gondwana side of Pangaea and spread across South Pangaea and then North Pangaea. The oldest dinosaur fossils have been found in South America, Madagascar, Africa and India, including Nyasasaurus and Eoraptor. These were followed by long-necked herbivorous sauropods like Gondwanatitan, and Cryolophosaurus and Australovenator Dinosaurs evolved in Gondwana. Eventually, during the age of reptiles, dinosaurs dominated the terrestrial world. While the first dinosaurs walked in southern Pangaea, their cousins, the pterosaurs, evolved in the north, took to the sky, and reached Gondwana while Pangaea still existed. The oceans surrounding Pangaea were dominated by marine reptiles such as mosasaurs and plesiosaurs. The supercontinent Pangaea began as a reptile world and ended as a reptile world.
About 180 million years ago, Pangaea split into Laurasia and Gondwana, with Gondwana again remaining alone in the Southern Hemisphere and remaining that way for the next 30 million years. Gondwana began to break up during the Cretaceous, the last period of the Age of Reptiles, but the breakup of Gondwana was a slow process. First Africa and South America separated from Madagascar, India, Antarctica, and Australia, creating two small continents. Soon after, South America and Africa separated, and India, leaving Madagascar behind, moved rapidly northward and collided with Asia. Dinosaurs continued to evolve on the separated landmasses, and as new seas and oceans formed among the remains of Pangaea, they became endemic (species unique to a particular place) in the areas where dinosaurs could no longer leave. On the remains of Gondwana, carnivorous dinosaurs such as Spinosaurus (Africa), Lapatur (Australia), Carnotaurus (South America), and Giganotosaurus (South America) preyed on herbivorous Titanosaurus (South America), Argentinosaurus (South America), and Antarctopelta (Antarctica and South America). In South America, the oldest marsupial, Patagorynchus, evolved alongside Beelzebufo (the devil toad), the largest frog that ever lived. The disappearance of Gondwana led to an increase in animal diversity, with predators and prey evolving in each landmass and adapting to the climatic conditions they needed to survive.
The final stage of Gondwana’s breakup occurred when Antarctica, Zealandia, and Australia separated, and eventually South America separated from Antarctica, forming the third and current ice cap in the last 500 million years on Antarctica at the South Pole. Ice ages that can support ice caps are rare and occur only when icehouse climate conditions occur, and ice ages are rare because icehouse conditions are fragile. Gondwana holds evidence of the end of two ice ages before Pangaea came into existence, both of which ended in extinction because climate change occurred faster than life’s ability to adapt. Today’s Quaternary Ice Age, in which we live and in which the entire evolution of humanity took place, is rapidly coming to an end. We can learn from Gondwana and realize that rapid climate change is never good for apex predators. And humans are the modern apex predators. But as we have already shown, we have the power to change the climate. We can choose to use that power, that knowledge, to manage climate conditions, to maintain our existence and the stability of the ecosystems on which we depend, and to create a climate in which human civilization can thrive equitably and sustainably. The animals in past mass extinctions did not have the choices that we humans created for them. They could only adapt to climate change rather than change it to support the ecosystems they depended on to survive.
If you want to learn more about Earth’s history, I highly recommend the following documentaries:
