Deborah Gordon studies ant colonies in the Arizona desert to understand their complex social system. She asks: How do these chitinous creatures get down to business -- and even multitask when they need to -- with no language, memory or visible leadership? Her answers could lead to a better understanding of all complex systems, from the brain to ...

Forget about the hybrid auto -- Shai Agassi says it's electric cars or bust if we want to impact emissions. His company, Better Place, has a radical plan to take entire countries oil-free by 2020.

"If I should have a daughter, instead of Mom, she's gonna call me Point B ... " began spoken word poet Sarah Kay, in a talk that inspired two standing ovations at TED2011. She tells the story of her metamorphosis -- from a wide-eyed teenager soaking in verse at New York's Bowery Poetry Club to a teacher connecting kids with the power of self-exp...

Neuroscientist Daniel Wolpert starts from a surprising premise: the brain evolved, not to think or feel, but to control movement. In this entertaining, data-rich talk he gives us a glimpse into how the brain creates the grace and agility of human motion.

Would you negotiate with someone you knew to be evil, to save lives? Samantha Power tells a story of a complicated hero, Sergio Vieira de Mello. This UN diplomat walked a thin moral line, negotiating with the world's worst dictators to help their people survive crisis. It's a compelling story told with a fiery passion.

Bill Gross, the founder of Idealab, talks about his life as an inventor, starting with his high-school company selling solar energy plans and kits. Learn here about a groundbreaking system for solar cells -- and some questions we haven't yet solved.

The face of nuclear terror has changed since the Cold War, but disaster-medicine expert Irwin Redlener reminds us the threat is still real. He looks at some of history's farcical countermeasures and offers practical advice on how to survive an attack.

Richard Dawkins urges all atheists to openly state their position -- and to fight the incursion of the church into politics and science. A fiery, funny, powerful talk.

Nuclear power: the energy crisis has even die-hard environmentalists reconsidering it. In this first-ever TED debate, Stewart Brand and Mark Z. Jacobson square off over the pros and cons. A discussion that'll make you think -- and might even change your mind.

Russell Foster is a circadian neuroscientist: He studies the sleep cycles of the brain. And he asks: What do we know about sleep? Not a lot, it turns out, for something we do with one-third of our lives. In this talk, Foster shares three popular theories about why we sleep, busts some myths about how much sleep we need at different ages -- and h...

Freedom from cars, freedom from sprawl, freedom to walk your city! City planner Jeff Speck shares his "general theory of walkability" -- four planning principles to transform sprawling cities of six-lane highways and 600-foot blocks into safe, walkable oases full of bike lanes and tree-lined streets.

At TED2010, Bill Gates unveils his vision for the world's energy future, describing the need for "miracles" to avoid planetary catastrophe and explaining why he's backing a dramatically different type of nuclear reactor. The necessary goal? Zero carbon emissions globally by 2050.

How might the human race end? Stephen Petranek lays out 10 terrible options and the science behind them. Will we be wiped out by an asteroid? Eco-collapse? How about a particle collider gone wild?

Cambridge researcher Aubrey de Grey argues that aging is merely a disease -- and a curable one at that. Humans age in seven basic ways, he says, all of which can be averted.

How can we bridge the gap between left and right to have a wiser, more connected political conversation? Journalist Gretchen Carlson and op-ed columnist David Brooks share insights on the tensions at the heart of American politics today -- and where we can find common ground. Followed by a rousing performance of "America the Beautiful" by Vy Hig...

Daniel Kraft offers a fast-paced look at the next few years of innovations in medicine, powered by new tools, tests and apps that bring diagnostic information right to the patient's bedside.

Too often, cancer treatments have a short-sighted focus on individual cells, says David Agus. He suggests a new, cross-disciplinary approach, using atypical drugs, computer modeling and protein analysis to diagnose and treat the whole body.

What if your job didn't control your life? Brazilian CEO Ricardo Semler practices a radical form of corporate democracy, rethinking everything from board meetings to how workers report their vacation days (they don't have to). It's a vision that rewards the wisdom of workers, promotes work-life balance — and leads to some deep insight on what wo...

Jane Goodall hasn't found the missing link, but she's come closer than nearly anyone else. The primatologist says the only real difference between humans and chimps is our sophisticated language. She urges us to start using it to change the world.

Why build a virtual world? Philip Rosedale talks about the virtual society he founded, Second Life, and its underpinnings in human creativity. It's a place so different that anything could happen.

We teach girls that they can have ambition, but not too much ... to be successful, but not too successful, or they'll threaten men, says author Chimamanda Ngozi Adichie. In this classic talk that started a worldwide conversation about feminism, Adichie asks that we begin to dream about and plan for a different, fairer world -- of happier men and...

When will the coronavirus vaccine be ready? Epidemiologist Seth Berkley (head of Gavi, the Vaccine Alliance) takes us inside the effort to create a vaccine for COVID-19. With clarity and urgency, he explains what makes it so challenging to develop, when we can expect it to be rolled out at scale and why we'll need global collaboration to get it ...

Accepting his 2005 TED Prize, photographer Edward Burtynsky makes a wish: that his images -- stunning landscapes that document humanity's impact on the world -- help persuade millions to join a global conversation on sustainability.

"The opposite of depression is not happiness, but vitality, and it was vitality that seemed to seep away from me in that moment." In a talk equal parts eloquent and devastating, writer Andrew Solomon takes you to the darkest corners of his mind during the years he battled depression. That led him to an eye-opening journey across the world to int...

Capitalism needs an upgrade, says PayPal CEO Dan Schulman, and it starts with paying people enough to actually invest in their futures. He discusses why companies need to cultivate trust to recover and rebuild after the COVID-19 pandemic -- and how we can use this defining moment to create a more inclusive, ethical economy. (This virtual convers...

Bill Gates talks best (and worst) case scenarios for the coronavirus pandemic in the months ahead, explaining the challenges of reducing virus transmission, providing an update on promising vaccine candidates, offering his thoughts on reopening and even taking a moment to address conspiracy theories circulating about himself. Stay tuned for his ...

The single most important thing for avoiding a climate disaster is cutting carbon pollution from the current 51 billion tons per year to zero, says philanthropist and technologist Bill Gates. Introducing the concept of the "green premium" -- the higher price of zero-emission products like electric cars, artificial meat or sustainable aviation fu...

"I'm a capitalist. I believe in the system. I believe you can increase the size of the pie and you could divide it well," says Ray Dalio, founder of Bridgewater Associates. He offers wide-ranging insight and advice on how we might recover from the global economic fallout of the coronavirus crisis -- and use it as an opportunity to reform the sys...