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Video transcript

NARRATOR: Eight dramatic transitions drive Big History's 13.7 billion-year story. We call these major Thresholds of Increasing Complexity. They are times when the right ingredients combined with just the right conditions to enable the creation of an entirely new form of complexity. When our Universe appeared, it was simple, and from our perspective, frankly, a bit boring. There were no stars, no planets, no life and certainly, no humans. And yet, look around, and you'll see amazing complexity. A sky filled with stars and galaxies in all stages of development. You'll see a solar system formed by the remnants of stars that were born and died billions of years ago. You'll see our own Earth filled with mountains and rivers, deep caverns and vast oceans, and incredible biodiversity. And you'll see our own innovative species, with our computers, airplanes and skyscrapers and our endless art and invention. Eight thresholds explain how a relatively simple Universe transformed into the rich complexity that's all around us today. Each threshold builds upon the previous one. Together they help explain where everything came from. They help explain our own place in the Universe and where things may be heading. Today, much of the Universe is still pretty simple with large tracts of empty space. We'll see how complex things appeared in special regions, regions where the ingredients and the Goldilocks conditions were just right to cross new thresholds of complexity. Step by step, we'll see how new forms of complexity appeared, each with components and qualities that had never been seen before, leading to the world we live in today.