TED Talks Daily (SD video)

Diébédo Francis Kéré knew exactly what he wanted to do when he got his degree in architecture… He wanted to go home to Gando in Burkina Faso, to help his neighbors reap the benefit of his education. In this charming talk, Kéré shows off some of the beautiful structures he's helped to build in his small village in the years since then, including an award-winning primary school made from clay by the entire community.

"In the cathedral of the wild, we get to see the best parts of ourselves reflected back to us." Boyd Varty, a wildlife activist, shares stories of animals, humans and their interrelatedness, or "ubuntu" -- defined as, "I am, because of you." And he dedicates the talk to South African leader Nelson Mandela, the human embodiment of that same great-hearted, generous spirit.

"An advanced city is not one where even the poor use cars, but rather one where even the rich use public transport," argues Enrique Peñalosa. In this spirited talk, the former mayor of Bogotá shares some of the tactics he used to change the transportation dynamic in the Colombian capital... and suggests ways to think about building smart cities of the future.

David Lang is a maker who taught himself to become an amateur oceanographer -- or, he taught a robot to be one for him. In a charming talk Lang, a TED Fellow, shows how he and a network of ocean lovers teamed up to build open-sourced, low-cost underwater explorers.

It's time for liberals and conservatives to transcend their political differences and really listen to each other, says political pundit Sally Kohn. In this optimistic talk, Kohn shares what she learned as a progressive lesbian talking head on Fox News. It’s not about political correctness, she says, but rather, emotional correctness. (Contains profanity.)

It's relatively easy to imagine a new medicine, a better cure for some disease. The hard part, though, is testing it, and that can delay promising new cures for years. In this well-explained talk, Geraldine Hamilton shows how her lab creates organs and body parts on a chip, simple structures with all the pieces essential to testing new medications -- even custom cures for one specific person. (Filmed at TEDxBoston)

Here's a stat worth knowing: In the UK, 63% of men who finish short-term prison sentences are back inside within a year for another crime. Helping them stay outside involves job training, classes, therapy. And it would pay off handsomely -- but the government can't find the funds. Toby Eccles shares an imaginative idea for how to change that: the Social Impact Bond. It's an unusual bond that helps fund initiatives with a social goal through private money -- with the government paying back the investors (with interest) if the initiatives work.

The one thing all humans have in common is that each of us wants to be happy, says Brother David Steindl-Rast, a monk and interfaith scholar. And happiness, he suggests, is born from gratitude. An inspiring lesson in slowing down, looking where you’re going, and above all, being grateful.

The human brain is puzzling -- it is curiously large given the size of our bodies, uses a tremendous amount of energy for its weight and has a bizarrely dense cerebral cortex. But: why? Neuroscientist Suzana Herculano-Houzel puts on her detective's cap and leads us through this mystery. By making "brain soup," she arrives at a startling conclusion.

There's an irony behind the latest efforts to extend human life: It's no picnic to be an old person in a youth-oriented society. Older people can become isolated, lacking meaningful work and low on funds. In this intriguing talk, Jared Diamond looks at how many different societies treat their elders -- some better, some worse -- and suggests we all take advantage of experience.

"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 happening right now.

A billion people in the world lack access to all-season roads. Could the structure of the internet provide a model for how to reach them? Andreas Raptopoulos of Matternet thinks so. He introduces a new type of transportation system that uses electric autonomous flying machines to deliver medicine, food, goods and supplies wherever they are needed.

Paralyzed by a stroke, Henry Evans uses a telepresence robot to take the stage -- and show how new robotics, tweaked and personalized by a group called Robots for Humanity, help him live his life. He shows off a nimble little quadrotor drone, created by a team led by Chad Jenkins, that gives him the ability to navigate space -- to once again look around a garden, stroll a campus … (Filmed at TEDxMidAtlantic.)

What are our forests really made of? From the air, ecologist Greg Asner uses a spectrometer and high-powered lasers to map nature in meticulous kaleidoscopic 3D detail -- what he calls “a very high-tech accounting system” of carbon. In this fascinating talk, Asner gives a clear message: To save our ecosystems, we need more data, gathered in new ways.

Ecologist Lian Pin Koh makes a persuasive case for using drones to protect the world's forests and wildlife. These lightweight autonomous flying vehicles can track animals in their natural habitat, monitor the health of rainforests, even combat crime by detecting poachers via thermal imaging. Added bonus? They're also entirely affordable.