Environmentalist John Francis speaks about the 17 years of his life during which he never spoke a word. Andrew Heavens/Courtesy of TED hide caption

itoggle caption Andrew Heavens/Courtesy of TED

"I began to learn at least what other people felt and what they wanted to say before cutting them off with my own diatribe. I used to do that." - John Francis Andrew Heavens/TED hide caption

itoggle caption Andrew Heavens/TED

"Clouds are the most egalitarian of nature's displays 'cause we all have a great view of the sky" - Gavin Pretor-Pinney James Duncan Davidson/TED hide caption

itoggle caption James Duncan Davidson/TED

Pipes for Transcanada Corp.'s planned Keystone XL oil pipeline are stacked at a depot in Gascoyne, N.D. The House of Representatives approved the Keystone XL pipeline Friday; the Senate voted against it on Tuesday. Andrew Cullen/Reuters/Landov hide caption

itoggle caption Andrew Cullen/Reuters/Landov

Pipes for TransCanada's planned Keystone XL pipeline are stored in Gascoyne, N.D. The U.S. House has voted to approve the proposed project, which would allow crude oil to flow from Canada to the Gulf of Mexico. The Senate plans to vote Tuesday on legislation that would greenlight the project. Andrew Cullen/Reuters/Landov hide caption

itoggle caption Andrew Cullen/Reuters/Landov

Sherri Erkel and her daughter, Asa, cook dinner in their kitchen in Iowa City, Iowa. The Erkel family is part of an EPA study measuring the amount of food wasted in U.S. homes. Pat Aylward/NET News hide caption

itoggle caption Pat Aylward/NET News

Lightning strikes near Ben Hill Griffin Stadium at Florida Field in Gainesville, Fla., in August. A new study says a rise in average global temperatures due to climate change will increase the frequency of lightning strikes. Phil Sandlin/AP hide caption

itoggle caption Phil Sandlin/AP