A protest of the Keystone XL pipeline last March along its proposed route near Bradshaw, Nebraska. NH/AP hide caption
Science
Friday
Pipefitters work on construction of the Keystone XL Pipeline's southern portion outside Tulsa, Okla., last January. PR Newswire hide caption
"People like to share, if you give them the opportunity and the choice." — John Wilbanks James Duncan Davidson/TED hide caption
A tasseled wobbegong shark (top) lies on the seafloor with the head of a brown-banded bamboo shark in its mouth on the fringing reef of Great Keppel Island on Australia's Great Barrier Reef in August 2011. Reuters/Landov hide caption
Thursday
Magellanic penguins strut their stuff on the rocky shoreline of Argentina's Punta Tombo, home to the largest colony of the birds in the world. Craig Lovell/Corbis hide caption
Charles, Prince of Wales, smells before tasting some ice cream during a visit to Gloucestershire. Maybe he was sniffing for fat? Barry Batchelor/Getty Images hide caption
Some men take testosterone hoping to boost energy and libido, or to build strength. But at what risk? iStockphoto hide caption
An artist's concept of a narrow asteroid belt orbiting a star similar to our own sun. NASA/JPL-Caltech hide caption
Gas flaring near Highway 85 southwest of Williston. Analysts estimate that almost 30 percent of the gas being produced in the state is burned off. Jeff Brady/NPR hide caption
Wednesday
Playing outside can help kids — and their parents — maintain a healthy weight. iStockphoto hide caption