Caption A captive desert woodrat, also known as a packrat, stands on a rock near branches from a toxic creosote bush. A new University of Utah study shows how microbes in the gut play a key role ...

This image shows a desert woodrat in a metabolism cage at the University of Utah. The cage allows researchers to measure how much food and water the rat consumes and how much waste it produces.

The imperiled Allegheny woodrat has been rediscovered at Harpers Ferry. On a muggy morning last June in the highlands of Harpers Ferry National Historical Park, Mack Frantz slowly approached a wire ...