Physicist Geoffrey West has found that simple, mathematical laws govern the properties of cities -- that wealth, crime rate, walking speed and many other aspects of a city can be deduced from a single number: the city's population. In this mind-bending talk from TEDGlobal he shows how it works and how similar laws hold for organisms and corporations.
Bees have been rapidly and mysteriously disappearing from rural areas, with grave implications for agriculture. But bees seem to flourish in urban environments -- and cities need their help, too. Noah Wilson-Rich suggests that urban beekeeping might play a role in revitalizing both a city and a species.
What would a sustainable, universally beneficial economy look like? "Like a doughnut," says Oxford economist Kate Raworth. In a stellar, eye-opening talk, she explains how we can move countries out of the hole -- where people are falling short on life's essentials -- and create regenerative, distributive economies that work within the planet's ecological limits.
