Explore the Earth’s History With This Supercontinents Quiz

Geologist Marie Tharp made history in 1953 when she discovered the Mid-Atlantic Ridge, a 10,000-mile-long underwater mountain range. In the midst of the range, she found a valley where two continental plates were drifting apart. This discovery supported Alfred Wegner’s theory of continental drift, and was the first big step toward scientific acceptance of plate tectonics.

The Mesosaurus, a freshwater crocodile-like reptile, lived between 286 million and 258 million years ago. Its fossils are found only in southern Africa and eastern South America. Since Mesosaurus is a freshwater reptile, it couldn’t have crossed the saltwater ocean between two continents, leaving fossils on both. This suggests that South Africa and South America were joined together during that period.

The Great Dying, also known as the Permian-Triassic extinction, is thought to have exterminated 96 percent of ocean life. Scientists have debated what precipitated the extinction event, but the most recent theory suspects a period of global warming. Since a warming climate causes decreased oxygen levels in oceans, it could explain the massive loss of marine life during the Great Dying.

Six supercontinents are believed to have existed on Earth before Pangea. The first was Vaalbara, which is thought to have formed 3.6 billion years ago, followed 300 million years later by Ur. The third supercontinent, Kenorland, was followed by Colombia, Rodinia, Pannotia, and lastly, Pangea.

The preserved tree logs at Petrified Forest National Park are the remnants of an ancient conifer forest that dates back approximately 225 million years. During the late Triassic period, when Pangea was still around, stream currents carried the logs into lowlands rich with volcanic ash, which preserved the logs. Over time, the wood was replaced by minerals and turned to stone.

The name Panthalassa also comes from ancient Greek, meaning “all seas.” Panthalassa began to separate into distinct oceans when Pangea broke apart. As the continents separated, they gouged massive valleys into the ocean floor, which filled up with water to become the five primary oceans we have today.

Pangea comes from the ancient Greek word meaning “all lands.” The supercontinent was named by Alfred Wegner, who first proposed the existence of Pangea in 1912 when he introduced his theory of continental drift.

Alfred Wegner came up with the idea of continental drift (what we now call plate tectonics) when he noticed the seven continents could fit perfectly like puzzle pieces, and must have at one point been joined together. When he announced his theory in 1912, he was publicly mocked, his ideas dismissed as “delirious ravings.” Not until the 1960s, after Wegner died, did geologists support the theory.

According to the theory of plate tectonics, the Earth’s crust and upper mantle are separated into large rocky plates. Sitting atop molten rock, the plates move over time and interact with each other to create geological formations such as mountain ranges and volcanoes. The theory was first proposed in the early 20th century, and is now commonly accepted by the scientific community.

Between 280 million and 230 million years ago, the current seven continents were all joined together as a single landmass, known as Pangea. On the geological time scale, Pangea spanned the late Paleozoic era to the late Triassic era. Eventually, the continent started to break apart, starting with Africa, South America, and North America, then Europe, Asia, Australia, and Antarctica.