Seagrass meadows provide food and shelter for myriad residents including the bay scallop, the charismatic West Indian manatee, the seahorse and the green turtle.
Credit: Clockwise from top left:Kimberly Petersen Manzo, www.seagrassli.org; Robert Stewart/Animals Animals; Chris Pickerell, www.seagrassli.org; Rich Carey/Istockphoto

Seagrasses, such as the Zostera shown at top, can grow in dense clumps. The close-up image at bottom left shows two tiny female flowers opening, with a male flower releasing white pollen in between the other two. At bottom right, filaments of pollen in Zostera marina float around fine metal forceps.
Credit: Top photo: Chris Pickerell, www.seagrassli.org; Bottom photos: J. Ackerman

Young environmental activists from around the world plead for a new agreement to reduce global greenhouse gas emissions during the 2007 U.N. Climate Change Conference in Bali, Indonesia.
Credit: Jewel Samad/AFP/Getty Images

Maps show most of Earth's land surface was warmer in September 2009 than the 100-year September average. That made this the second warmest September on land since records began in 1880.
Credit: NOAA

The McCall glacier in Alaska's Arctic National Wildlife Refuge has undergone accelerating ice loss in recent decades.
Credit: From top: Austin Post, Matt Nolan; Both: National Snow & Ice Data Center

China, which recently surpassed the United States in total (not per capita) greenhouse gas emissions, is trying to improve energy efficiency. Workers install a solar roof (left) and a man charges an electric car (right).
Credit: AP; Kevin Lee/Bloomberg/Getty Images

A vendor in Kenya charges phones and lanterns using electricity from renewable energy. Several African nations have clean-energy goals.
Credit: Simon Maina/AFP/Getty Images

Now, I think people are starting to realize this ability of bacteria to interact with the environment in an electrical way.
Credit: Philip Channing/USC College

This unusually deep feature on the moon (in box) is 65 meters wide and may be a portal into an underground cavern that once held flowing lava.
Credit: Haruyama et al./Geophysical Research Letters

The queen of a leaf-cutter colony visits one of the ants' gardens, where green leaf bits feed the pale, spongy fungus that in turn can feed several million ants in a mature colony. A queen can live 15 years and lay some 200 million eggs.
Credit: Michael Poulsen, Science/AAAS

Leaf cutter ants slice foliage into bits that they can carry back to their nests. The ants can't digest the leaves themselves but have what amounts to an external gut, a mix of fungi and nitrogen-fixing bacteria that do the work.
Credit: Jarrod Scott, Science/AAAS

Corn’s amazing diversity is not just kernel deep: The near-complete genome of maize reveals a surprising amount of genetic diversity, even between strains of the crop plant.
Credit: Science/AAAS