Trace elements in the carbonate shells of freshwater mussels could serve as an archive of road salt pollution.

Unusual data let scientists test predictions that global warming drives species up slopes.

Recent fossil discovery shows that new species of arthropod formed chains, raising the possibility of communal behavior.

Analyses of trees and other organic material buried in a riverbank near Lake Superior’s northwestern shore shed new light on how much and when the lake level varied soon after the last ice age.

Paleontologists and aeronautical engineers are designing a reconnaissance drone that will mimic the flight of an ancient flying reptile.

The NASA MESSENGER spacecraft completed its second flyby of Mercury, yielding crisp new images of a large swath of the planet not seen before.

Seven immense coral boulders — one of them a three-story-tall, 1,200-metric-ton monster — have been found far inland on a Tongan island and may be the world's largest tsunami debris.

Fossils of trees that grew in Antarctica millions of years ago suggest a growth pattern much different than modern trees.

Where stalagmites start and stop in caves could offer more precise clues about when major earthquakes have hit (and could again hit) the Midwest.

This summer, the area covered by Arctic sea ice dropped to its second-lowest since satellite measurements began in 1979.

For the first time, researchers have assembled a comprehensive record of how sea level varied between 542 million and 251 million years ago, more than doubling previous timelines for such fluctuations.

Featured blog: Switching to light bulbs that contain mercury might, surprisingly, reduce overall mercury releases to the environment. Plus, what to do when you break your fluorescent bulb.

As mission nears end, Phoenix Mars Lander finds strong evidence for minerals similar to those formed on Earth by liquid water. (p. 13)

Scientists have uncovered a new dinosaur that breathed like a bird. (p. 14)

The stony meteorite that landed in a remote portion of Peru in September 2007 was traveling abnormally fast when it struck and blasted a crater that was unusually large for the its size, new analyses indicate.