Science

Wildlife photographer Nick Nichols remembers a close call with a tigress.

We reintroduce animals to their native habitat as part of an impulse to re-create “wilderness” — a place untouched by man. The result is more like the feeling of wilderness.

A hidden world of pathways leads wild animals safely across busy roads, keeping ecosystems connected even as human use fragments and disturbs them.

Since the 1950s, a timber company has used conservation-driven logging to balance productive use and wild forests.

There's no way to predict what strain of the shape-shifting flu virus could trigger another pandemic or, given modern medical tools, how bad it might be.

Of the remaining cohort of Earthlings privileged to set foot on the moon, let’s extend 88th birthday greetings this week to Buzz Al ...

More than two dozen wind farms popped up across the state leading up to 2012, but only one in the years since.

The case is centered on a 2014 ban and a subsequent municipal charter adopted by Grant Township that banned fracking wastewater injection projects.

The settlement pertains to 10 coal-fired power plants around the state that have been operating on expired water pollution permits for years — in one case for 17 years.

More than 3.4 million Pennsylvanians are supplied by drinking water containing radium that exceeds a strict California standard, which advocates say should replace a looser fe