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.

In this hilariously lively performance, actress Sarah Jones channels an opinionated elderly Jewish woman, a fast-talking Dominican college student and more, giving TED2009 just a sample of her spectacular character range.

Local politics -- schools, zoning, council elections -- hit us where we live. So why don't more of us actually get involved? Is it apathy? Dave Meslin says no. He identifies 7 barriers that keep us from taking part in our communities, even when we truly care.

Worldchanging.com founder Alex Steffen argues that reducing humanity’s ecological footprint is incredibly vital now, as the western consumer lifestyle spreads to developing countries.

Why do people distrust vaccines? Anthropologist Heidi Larson explores how medical rumors originate, spread and fuel resistance to vaccines worldwide. While vaccines cannot escape the "political and social turbulence" that surrounds them, she says, the first step to stopping the spread of disease is to talk to people, listen and build trust.

William Ury, author of "Getting to Yes," offers an elegant, simple (but not easy) way to create agreement in even the most difficult situations -- from family conflict to, perhaps, the Middle East.

How can we unlock the door to our own authentic sexual well-being? Sex educator Emily Nagoski suggests that the key is realizing that we are all normal, whatever our proclivities. In this playful but informative take on sex positivity, she delves into the science of sexuality to demonstrate how we can shed our insecurities and define pleasure on...

Remember the Ice Bucket Challenge craze this summer? Meet the mom who started it all. When Nancy Frates's son Pete hurt his wrist in a baseball game, he got an unexpected diagnosis: it wasn’t a broken bone, it was ALS, and there is no cure. In this inspiring talk, Nancy tells the story of what happened next.

"Life comes at us very quickly, and what we need to do is take that amorphous flow of experience and somehow extract meaning from it." In this funny, enlightening talk, educational psychologist Peter Doolittle details the importance -- and limitations -- of your "working memory," that part of the brain that allows us to make sense of what's happ...

Daniel Goleman, author of "Emotional Intelligence," asks why we aren't more compassionate more of the time.