NASA's Molly Brown developed a Famine Early Warning System Network. Brown talks about this life-saving technology in this 8-minute podcast.

India is now the world's second-most-populated country, next to China.

David Carroll is getting closer to creating a new kind of solar cell, one made of plastic that would be lightweight, flexible, and more efficient than the more familiar silicon solar cells. Read more about how nanotechnology is improving solar cell efficiency.

He has created a device that could help doctors identify what are called "oncoproteins." This research might eventually enable doctors to better diagnose and treat early-stage cancer.

It seems obvious there's economic value in nature's raw potential for goods. But nature has other, perhaps less obvious, economic value, said economist Scott Barrett.

Ethno-botanist Darron Collins talks about rainforest logging. It may be more sustainable, but it'll take much more to save the rainforests. Read more.

Partha Dasgupta told Earth & Sky that, in the developing world, natural resources aren't just amenities. Instead, they're economic necessities.

Scientists are now speaking of what they call the "coupled human-environment system." It's a new way of thinking about the relationship between nature and human beings.

Kai Lee said, "I think one of the great dilemmas we face is acknowledging this interdependence in a way which also enables us to live our lives. We don't want to be encumbered all the time with thinking about all the indirect consequences of what we're doing in the world. And I think that's a dilemma that we don't even recognize is a dilemma yet ... "

Urbanites soon to outnumber country dwellers