You can’t photograph the inside of a twister, but radar offers some clues.

A computer security expert explains how keys work – and how they are like passwords.

The Earth is a resilient planet, but people are altering it in ways that may take centuries to reverse.

A veterinary ophthalmologist explains what’s going on.

The dwarf planets in our Solar System are cold, dark, far away and full of surprises.

Cockroaches have been on Earth far longer than humans and may outlast us. Here are a few reasons why.

These coordinated movements of a flock of starlings follow no plan or leader. Scientists used to think the animals must communicate via ESP to create these fast-moving blobs.

Hard and strong, or bendy and flexible? A cartilaginous skeleton provides advantages in the ocean, but wouldn’t stand up to life on land.

Poop comes in many shapes, sizes and textures. The kind that’s too runny might be the result of wayward germs, Crohn’s disease or lactose intolerance.

That brownish/yellowish gunk that comes out on your finger if you scratch deep inside your ear? It actually serves an important purpose in your body.