Emma Marris is a writer focusing on environmental science, policy and culture, with an approach that she paints as being "more interested in finding and describing solutions than delineating problems, and more interested in joy than despair."
Stefano Mancuso is a founder of the study of plant neurobiology, which explores signaling and communication at all levels of biological organization, from genetics to molecules, cells and ecological communities.
Called "the queen of canopy research," Nalini Nadkarni explores the rich, vital world found in the tops of trees. She communicates what she finds to non-scientists -- with the help of poets, preachers and prisoners.
Iqbal Quadir is an advocate of business as a humanitarian tool. With GrameenPhone, he brought the first commercial telecom services to poor areas of Bangladesh. His latest project will help rural entrepreneurs build power plants.
Penny Chisholm studies an extremely tiny microorganism that plays an enormous role in ocean ecosystems. Discovered only three decades ago, it has defined her career and inspired her to think differently about life on Earth.