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Gondwana was an ancient continent made up of much of present-day South America, Africa, Madagascar, India, Australia, and Antarctica. It formed over a long period and reached almost complete form 500 million years ago. It was devoid of life and covered by shallow seas. Gondwana collided with other continents to form Pangea, which broke up about 200 million years ago, leaving Gondwana alone. It began breaking up in the Middle Jurassic and didn’t break up completely until Australia separated from Antarctica about 23 million years ago.
Gondwana, formerly called Gondwanaland, is an ancient and very large continent made up of much of present-day South America, Africa, Madagascar, India, Australia and Antarctica. It takes its name from the Gondwana region of northern India, one of the earliest fossil sites on the continent. Gondwana was formed over a long period of time, finally reaching an almost complete form about 500 million years ago, during the early Cambrian period.
Gondwana was so vast that the only major land bodies not part of it were northern and southern China (separate microcontinents at the time), Siberia, Baltica (present-day Europe), and Laurentia (the craton that includes current -day USA, Canada and Greenland). Laurentia and Gondwana were separated by the small Iapetus Sea, and more than 90% of Earth’s land mass was concentrated in the Southern Hemisphere. The vast sea to the north was known as the Panthalassic Sea, meaning “all seas”. During this time, an evolutionary radiation explosion called the Cambrian explosion was occurring, and the forerunners of all modern animal phyla emerged.
500 million years ago, Gondwana – and the rest of the earth – was devoid of life, consisting of nothing but desert, badlands and mountains. At that time, due to the layout of the continents, there were no ice caps and the world was quite warm. When continents have a lopsided configuration around the poles, it prevents a cold pool from forming, as ocean currents moving through the area bring heat from tropical latitudes. Since there were no ice caps, sea levels were quite high and there was only 60% of the landmass there is today. Most of Gondwana was then covered by shallow seas. These warm, shallow seas were ideal for the abundant marine life that evolved during this time.
The first colonization of earth by life is thought to have occurred during the Silurian, about 444-420 million years ago. At that time, the predominant life form on land were mosses, accompanied by some primitive vascular plants and arthropods. During the Devonian, 420-360 million years ago, land on life began to explode, with the first true forests creating soils. Amphibians and arthropods have colonized the coasts in large numbers, where they are reflected in the fossil record.
About 350 to 250 million years ago, Gondwana had large areas covered by glaciers. About 250 million years ago, Gondwana collided with the other continents to form Pangea, a supercontinent made up of most of the mainland. Pangea broke up about 200 million years ago, shortly after the evolution of the dinosaurs, again leaving Gondwana alone.
Gondwana itself began breaking up in the Middle Jurassic, about 167 million years ago, and didn’t break up completely until Australia separated from Antarctica about 23 million years ago. Today, older species of plants found in multiple locations in South Africa, Chile, and Australia are said to have a “Gondwanan distribution.”
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