Most beachgoers know that live jellyfish can be dangerous, but what if you encounter a dead one washed up on the shore? An expert weighs in on what to do.

Jellyfish are known for drifting to and fro at the whim of ocean currents—but not all species are so passive. The millions of golden jellyfish that pack Palau’s Jellyfish Lake spend much of ...

a girl exclaims. “I think they’re just mesmerizing,” Jennie Janssen, the assistant curator who oversees the care of the aquarium’s jellyfish, tells me. “They don’t have a brain, ...

Others, like the hippos introduced to Colombia about 30 years ago, pose threats to the native wildlife they coexist with. While there have not yet been any major problems identified that are linked to ...