TED-Ed

Explore the ever-evolving structure of the Milky Way galaxy, and find out how it got its spiral shape.--Thirteen billion years ago, the gas and dust particles that eventually became our Milky Way were whizzing around in every direction. Despite the wild motion of its parts, the galaxy as a whole was rotating about an axis. So why did the Milky Way, like most galaxies, become flat, and not spherica...

Travel to some of the most extreme environments on Earth and see how insects are able to employ their skills to survive.--Insects are the world’s most numerous and diverse animals. Even where you’d least expect them in some of Earth’s most extreme environments, there they are. From a scalding volcano, parched desert, to a frigid glacier, insects are living life on the edge. So, how do they do it?...

Every day there are news reports of new health advice, but how can you know if they're right? Doctor and epidemiologist Ben Goldacre shows us, at high speed, the ways evidence can be distorted, from the blindingly obvious nutrition claims to the very subtle tricks of the pharmaceutical industry. Talk by Ben Goldacre. Learn more about your ad choices. Visit megaphone.fm/adchoices

View full lesson: http://ed.ted.com/lessons/if-superpowers-were-real-immortality-joy-linWhat if immortality wasn't just the stuff of epic comic book stories? Is it scientifically possible to be immortal? In this series, Joy Lin tackles six superpowers and reveals just how scientifically realistic they can be to us mere mortals. Lesson by Joy Lin, animation by Cognitive Media. Learn more about your...

Take a peek beneath the ocean’s covers to discover the surprisingly inventive ways marine animals have sex.--On a reef in the Pacific Ocean, 17,000 camouflage groupers dart about in the cloudy water. It is, in fact, an underwater orgy— turned feeding frenzy. An orgy might seem like a rather flamboyant way to breed, but sex in the sea is a surprisingly inventive affair. So what other sneaky escapad...

View full lesson: http://ed.ted.com/lessons/how-did-trains-standardize-time-in-the-united-states-william-heuislerIf you live in the United States, you may live in the Eastern Standard Time Zone. Or maybe you live in Mountain Standard Time or one of the other standardized time zones. But these time zones have not always been around. In fact, it's a fairly recent development. William Heuisler explai...

View full lesson: http://ed.ted.com/lessons/earth-s-mass-extinction-peter-wardAsteroid strikes get all the coverage, but "Medea Hypothesis" author Peter Ward argues that most of Earth's mass extinctions were caused by lowly bacteria. The culprit, a poison called hydrogen sulfide, may have an interesting application in medicine. Talk by Peter Ward. Learn more about your ad choices. Visit megaphone....

They're the second largest fish in the world, they're almost extinct, and we know almost nothing about them. In this talk, Simon Berrow describes the fascinating basking shark ("Great Fish of the Sun" in Irish), and the exceptional -- and wonderfully low-tech -- ways he's learning enough to save them. (Filmed at TEDxDublin.)Talk by Simon Berrow. Learn more about your ad choices. Visit megaphone.fm...

Dig into the Greek myth of Achilles, and follow the infamous warrior during the Trojan War and see what leads to his downfall.--Born to a sea nymph and a king, and trained by the legendary centaur Chiron, Achilles was a demigod destined for greatness. When Greece declared war on Troy, Achilles knew the war was written into his destiny. With horses born from the west wind and a spear wrought from a...

View full lesson: http://ed.ted.com/lessons/do-the-green-thing-andy-hobsbawmAndy Hobsbawm shares a fresh ad campaign about going green -- and some of the fringe benefits. Talk by Andy Hobsbawm. Learn more about your ad choices. Visit megaphone.fm/adchoices

View full lesson: http://ed.ted.com/lessons/what-if-we-could-look-inside-human-brains-moran-cerfThe brain is what makes us function, yet we understand so little about how it works. We are learning more about the brain by using new technology to monitor epilepsy patients during surgery. Moran Cerf explains the process doctors use to explore the brain further. Lesson by Moran Cerf, animation by Buzz...

Dig into Toni Morrison’s novel, "Beloved," which tells the story of a family of formerly enslaved people whose home is haunted by an abusive spirit. --Two tiny handprints stamped into a cake. A mirror that shatters without warning. A trail of cracker crumbs strewn along the floor. Everyone at 124 Bluestone Road knows their home is haunted— but there’s no mystery about the spirit tormenting them. S...

Explore how heat waves affect the body, what levels of extreme heat we can survive, and what you can do to manage high temperatures.--In many parts of the world heat waves are happening more often with greater intensity and for longer durations. By 2050, Earth’s mid-latitudes could be experiencing extreme heat between 90 and 180 days a year, with tropical regions enduring even more. So how hot is...

Explore the toxicity of death cap mushrooms, and find out what makes this one species so dangerous to humans.--Humans have known about the toxicity of death cap mushrooms for millennia. Yet they continue to pose a significant threat to unsuspecting foragers and mushroom hunters throughout the world. Today, death caps are responsible for more than 90% of all mushroom related deaths, killing upwards...

In this series, Joy Lin tackles six superpowers and reveals just how scientifically realistic they can be to us mere mortals. Lesson by Joy Lin, animation by Cognitive Media. Learn more about your ad choices. Visit megaphone.fm/adchoices

Explore the model minority stereotype, and discover how it became a label for Asian Americans and is used to enforce racial hierarchies.--In 2007, researchers surveyed 180 teachers to understand if they held stereotypes about their students. The most commonly held opinion was that Asian students were significantly more industrious, intelligent, and gentle. This might seem like a good thing, but tr...

View full lesson: http://ed.ted.com/lessons/life-of-an-astronaut-jerry-carrAstronaut Jerry Carr knows space. As commander of Skylab, he spent over 2000 hours in space, orbiting the Earth over 1000 times. Recounting his life story, Carr remembers the enchanting years he spent at NASA.Lesson by Jerry Carr, animation by Sharon Colman Graham. Learn more about your ad choices. Visit megaphone.fm/adchoi...

How much land mass would renewables need to power a nation like the UK? An entire country's worth. In this pragmatic talk, David MacKay tours the basic mathematics that show worrying limitations on our sustainable energy options and explains why we should pursue them anyway. (Filmed at TEDxWarwick.)Lesson by David MacKay. Learn more about your ad choices. Visit megaphone.fm/adchoices

Follow Sun Wukong, the Monkey King, on his journey to Heaven and the trouble he causes the Jade Emperor during his stay.--While his disciples loved their roguish leader, Sun Wukong’s misadventures had spread chaos throughout the land. The Jade Emperor, watching from his throne in Heaven, decided he would no longer stand by as this monkey wreaked havoc across his domain. The Emperor decided the bes...

Explore the physics behind space elevators, which would theoretically use a cable anchored to Earth and extending into space. --Sending rockets into space requires sacrificing expensive equipment, burning massive amounts of fuel, and risking potential catastrophe. So in the space race of the 21st century, some engineers are abandoning rockets for something more exciting: elevators. What would it t...

Jarreth Merz, a Swiss-Ghanaian filmmaker, came to Ghana in 2008 to film the national elections. What he saw there taught him new lessons about democracy -- and about himself. Talk by Jarreth Merz. Learn more about your ad choices. Visit megaphone.fm/adchoices

Simon Sinek has a simple but powerful model for inspirational leadership all starting with a golden circle and the question "Why?" His examples include Apple, Martin Luther King, and the Wright brothers ... (Filmed at TEDxPugetSound.)Talk by Simon Sinek. Learn more about your ad choices. Visit megaphone.fm/adchoices

View full lesson: http://ed.ted.com/lessons/in-on-a-secret-that-s-dramatic-irony-christopher-warnerYou're in a movie theater, watching the new horror flick. The audience knows something that the main character does not. The audience sees the character's actions are not in his best interest. What's that feeling -- the one that makes you want to shout at the screen? Christopher Warner identifies thi...

Discover what happened when one company's attempt to dominate a key global trade ended in violence.--During the 17th century, the Dutch East India Company cornered the booming spice market and pioneered trade routes between Asia and Europe. It is widely considered the most profitable corporation ever created. But such success came with an overwhelming cost in human life. Adam Clulow sheds light on...

Explore the science of afterimages, which are the visual illusions that appear in the eyes after exposure to an image or bright light.--In the 1600s, Isaac Newton conducted a series of experiments to better understand the lights and colors that sometimes appear when your eyes are closed. If you’ve ever sat around an evening campfire or unintentionally glanced at the Sun, you may have noticed illum...