Speaker 1: Welcome to brain Stuff production of iHeartRadio. Hey brain Stuff,
Speaker 1: Lauren Vogel bomb here. Sometimes good science can happen just
Speaker 1: by looking at a map of the world and letting
Speaker 1: your mind wander. For instance, observe how Africa and South
Speaker 1: America seem to have been very recently cuddled together, even
Speaker 1: though there are currently a couple of thousand miles of
Speaker 1: ocean between them. Similarly, Madagascar fits perfectly into a little
Speaker 1: nick in the eastern edge of Africa, and the Middle
Speaker 1: East seems to be pulling away from the top of
Speaker 1: Africa like a corner being pulled off of a hot cookie.
Speaker 1: With a reasonably good representation of the shape and arrangement
Speaker 1: of the world's continents in front of them, anyone could
Speaker 1: easily assess that the Earth's land masses have definitely been
Speaker 1: sneaking around. The name for the southern land mass that
Speaker 1: once was is Gondwana Land, also known as Gondwana. But
Speaker 1: it wasn't just the shape of the continents that cluded
Speaker 1: researchers into its former existence. They've also looked at similarities
Speaker 1: among plants and animals that live across the modern separate continents.
Speaker 1: From those clues, Gondwana was an idea long before anybody
Speaker 1: figured out how or why it worked, the secret, of
Speaker 1: course being plate tectonics, an idea that didn't really start
Speaker 1: gaining steam until the mid twentieth century. But a nineteenth
Speaker 1: century Austrian geologist named Edward Seuss put a name to
Speaker 1: the concept of the supercontinent in his book The Face
Speaker 1: of the Earth, the first volume of which was published
Speaker 1: in eighteen eighty three. SEUs didn't come up with many
Speaker 1: completely novel ideas, but he did a great job of
Speaker 1: synthesizing a bunch of the research of the day to
Speaker 1: conclude that the southern continents and land masses we now
Speaker 1: know as South America, Africa, Arabia, India, Sri Lanka, and
Speaker 1: Madagascar had at one point in time been connected because one, well,
Speaker 1: just look at them, and two they contained the same
Speaker 1: rocks and the same fossils from an extinct feathery leaked
Speaker 1: tree called Glosso Terraces. Austria and Antarctico would be added
Speaker 1: to the theory thirty years later. Gondwana was named for
Speaker 1: a densely forested region of central India where the first
Speaker 1: fossil evidence of the supercontinent was found. In the nineteenth century.
Speaker 1: Juana is a word for forest in Sanskrit, and the
Speaker 1: Gonds are tribe that European explorers first found living in
Speaker 1: the region. Even though we now know a lot about
Speaker 1: the mechanism by which Gondwana was formed, it's extremely complicated
Speaker 1: and still being investigated. There's at least one peer reviewed
Speaker 1: scientific journal devoted entirely to the study of the supercontinent.
Speaker 1: It's called appropriately Gondwana Research. However, there are a few
Speaker 1: things that were pretty certain of. First. Gondwana wasn't built
Speaker 1: in a day. The making of Gondwana was a long process,
Speaker 1: most likely through three major mountain building events driven by
Speaker 1: the movement of Earth's tectonic plates. We spoke via email
Speaker 1: with Joseph Merritt, a professor in the Department of Geological
Speaker 1: Sciences at the University of Florida. He explained, during the
Speaker 1: interval from about six dred and fifty two five hundred
Speaker 1: and fifty million years ago, various pieces of Africa and
Speaker 1: South America collided along an ancient mountain chain called the
Speaker 1: Braziliano Belt, slightly older but overlapping with the Braziliano seven
Speaker 1: fifty to six hundred and fifty million years ago, is
Speaker 1: the East African Oregon or Mozambique Belt that resulted from
Speaker 1: the collision between East Africa and Madagascar, India, Sri Lanka,
Speaker 1: and parts of East Antarctica. The final collision was along
Speaker 1: the Quanga Oregon between all those assembled pieces and the
Speaker 1: rest of Antarctica and Australia between five hundred eighty and
Speaker 1: five hundred thirty million years ago. So it was a
Speaker 1: couple hundred million years of extremely slow continental car wrex
Speaker 1: that created this beta version of Gondwana. But it wasn't
Speaker 1: done yet. Later, about three hundred million years ago, other
Speaker 1: land masses would join forces with it to form the
Speaker 1: giant ball of land we now know as Pangaea. But
Speaker 1: one continent to rule them all couldn't last, and sometime
Speaker 1: between two hundred and eighty and two hundred million years ago,
Speaker 1: panned has started disintegrating as magma began pushing up from
Speaker 1: beneath this mega supercontinent, creating riffs in the land that
Speaker 1: would later become sea floor. As Pangia cracked, the top
Speaker 1: part was pushed to the north, creating the continent laur
Speaker 1: Asia and Gondwana headed south back when Gondwana was just
Speaker 1: a baby Supercontinent between five hundred and fifty and four
Speaker 1: eighty five million years ago. It hosted some of the
Speaker 1: very first complex life forms, like child bites and brachiopods,
Speaker 1: but since it continued to exist into the Jurassic Period,
Speaker 1: lots of plant and animal evolution went down there. Merritt said,
Speaker 1: Gondwana contains evidence for evolutionary changes in the very first
Speaker 1: complex animals, the very first fish, amphibians, and reptiles. The
Speaker 1: most famous fossils are the Gondwana flora, such as the
Speaker 1: glasso terrace fern, a freshwater reptile called Mesosaurus, and a
Speaker 1: land reptile called Lystrosaurus. Gondwana existed as a single land
Speaker 1: mass for more than three hundred million years because of
Speaker 1: its Hu Monga's size, but it covered an area of
Speaker 1: a hundred billion square kilometers or about thirty nine billion
Speaker 1: square miles, and because the continents moved a lot during
Speaker 1: that time, Gondwana experienced many different climates. Merit said. During
Speaker 1: the Cambrian, when Gondwana first formed, the Earth and Gondwana
Speaker 1: were in a greenhouse state. In the late Ordovician four
Speaker 1: fifty billion years ago, Gondwana was moving over the South
Speaker 1: Pole and the climate was very cold. Gondwana continued to
Speaker 1: move through a variety of latitudes, and depending on where
Speaker 1: you were located, the climate might have been quite warm
Speaker 1: or more temperate. The continent was so large that one
Speaker 1: part of Gondwana might be located at the equator while
Speaker 1: another might be located at the pole. It's true it
Speaker 1: would have been cool to see Gondwana in its prime,
Speaker 1: and although you won't personally get to see its victorious return,
Speaker 1: that doesn't mean that it's not possible. The continents are
Speaker 1: always moving and scientists have a lot of ideas. But
Speaker 1: what our next supercontinent is going to look like? H
Speaker 1: Today's episode was written by Jesslyn Shields and produced by
Speaker 1: Tyler Clang. Brain Stuff is production of I Heart Radios,
Speaker 1: How Stuff Works. For one and this and lots of
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