New research shows that a fossilized plant from the Green River Formation is even stranger than scientists originally thought ...

FLAGSTAFF, Ariz.—The Federal Energy Regulatory Commission has accepted a preliminary permit application for a 24-story dam spanning the Little Colorado River gorge on the Navajo Nation. The proposed ...

The razorback sucker is a large, warm-water fish native to the Colorado River basin. Construction of more than a dozen dams throughout the lower basin has left little natural habitat ... to protect ...