A massive environmental calamity rocked the ancient Mediterranean. It took millions of years for the ecosystem to recover.

In Hawai‘i, people, pigs, and ecosystems only have so much room to coexist, and the pigs exist a little too much.

A sea cave on the northwest tip of Tonga’s Kapa Island is my favorite place on Earth. Nothing compares to freediving in the vibrant blue waters of Swallows Cave as beams of light and schools of fish ...

One Great Shot: Are You Ready for This, Jelly? During a nighttime dive, a veteran underwater photographer captured a tiny fish’s cunning effort to find a safe spot in a dark sea.