At up to 368 feet (112 meters) and 1,500 years old, redwoods are among the world's tallest and oldest living trees. Researchers are struggling to understand and protect these natural treasures.
Jagged flashes and tangled bolts are released from clouds in dramatic displays. Light up your screen with these high voltage shots from around the world.
Learn how our appetite may be destroying entire species of fish, shrimp, mollusks, marine turtles, and more, in this eye-opening gallery on overfishing.
Signs of and solutions to the world's water crisis.
Photo Tip of the Week
Natural Framing
Door frames, clouds, flowers—anything you see in your image can help to naturally frame your subject and create a strong visual center in your photo.