The Republic's climate reporter started her journey on the Arizona Trail with detours that were forced by wildfires and left ...

A study led by University of Arizona researchers shows that decades of groundwater pumping by humans has depleted Tucson-area ...

A set of fossilized footprints discovered in northern Arizona has revealed the silent journey of a prehistoric arachnid that walked the Earth around 260 million years ago. Preserved in stone, these ...

California's leading Democrats are grappling with how to confront lost jobs and high gas prices that the oil industry says are the result of the state's climate policies.

A planned shutdown of Valero's massive refinery near San Francisco in the spring would really put the pinch on motorists.

Grab an umbrella — tropical moisture from the remnants of Hurricane Priscilla pushed into Arizona, bringing days of showers and cooler temperatures.

Grab an umbrella — tropical moisture from Hurricane Priscilla pushes into Arizona, bringing several days of showers and cooler temperatures.

THE HAGUE (Reuters) -The Netherlands said it would give back a major fossil collection to Indonesia, granting its former colony's request to recover historical artefacts, including bones of the "Java ...

The surrounding town of Holbrook offers additional attractions for the curious traveler looking to extend their Route 66 adventure. This small Arizona community embraces its heritage with several ...

A strange Cambrian fossil named Salterella may hold the key to understanding how early animals first built skeletons. As the ...