"Venus is too hot, Mars is too cold, and Earth is just right," says planetary scientist Dave Brain. But why? In this pleasantly humorous talk, Brain explores the fascinating science behind what it takes for a planet to host life -- and why humanity may just be in the right place at the right time when it comes to the timeline of life-sustaining planets.

African growth is a trend, not a fluke, says economist and former Finance Minister of Nigeria Ngozi Okonjo-Iweala. In this refreshingly candid and straightforward talk, Okonjo-Iweala describes the positive progress on the continent and outlines eight challenges African nations still need to address in order to create a better future.

Our poop and pee have superpowers, but for the most part we don't harness them. Molly Winter faces down our squeamishness and asks us to see what goes down the toilet as a resource, one that can help fight climate change, spur innovation and even save us money.

If you want to build a business that lasts, there may be no better place to look for inspiration than your own immune system. Join strategist Martin Reeves as he shares startling statistics about shrinking corporate life spans and explains how executives can apply six principles from living organisms to build resilient businesses that flourish in the face of change.

Machine learning isn't just for simple tasks like assessing credit risk and sorting mail anymore -- today, it's capable of far more complex applications, like grading essays and diagnosing diseases. With these advances comes an uneasy question: Will a robot do your job in the future?

"A forest is much more than what you see," says ecologist Suzanne Simard. Her 30 years of research in Canadian forests have led to an astounding discovery -- trees talk, often and over vast distances. Learn more about the harmonious yet complicated social lives of trees and prepare to see the natural world with new eyes.

Neuroengineer Ed Boyden wants to know how the tiny biomolecules in our brains generate emotions, thoughts and feelings -- and he wants to find the molecular changes that lead to disorders like epilepsy and Alzheimer's. Rather than magnify these invisible structures with a microscope, he wondered: What if we physically enlarge them and make them easier to see? Learn how the same polymers used to make baby diapers swell could be a key to better understanding our brains.

Gerard Ryle led the international team that divulged the Panama Papers, the 11.5 million leaked documents from 40 years of activity of the Panamanian law firm Mossack Fonseca that have offered an unprecedented glimpse into the scope and methods of the secretive world of offshore finance. Hear the story behind the biggest collaborative journalism project in history.

eL Seed fuses Arabic calligraphy with graffiti to paint colorful, swirling messages of hope and peace on buildings from Tunisia to Paris. The artist and TED Fellow shares the story of his most ambitious project yet: a mural painted across 50 buildings in Manshiyat Naser, a district of Cairo, Egypt, that can only be fully seen from a nearby mountain.

We're heading for a world population of 10 billion people -- but what will we all eat? Lisa Dyson rediscovered an idea developed by NASA in the 1960s for deep-space travel, and it could be a key to reinventing how we grow food.