They can flow like a liquid and bounce back like a solid. Masses of fire ants show a duality that intrigues physicists.

Why do some of the national parks in the United States resemble the European Alps? Geologist Dr. Robert Darga answers this question.

Why are some rock formations and animals found on more than one continent? The explanation dates back to the Ice Age.

In this segment, the narrator explains where the name Bryce Canyon came from, and why the sand dunes in the US and the large deserts of the world might be related.

The narrator explains how the breathtaking rock formations of Antelope Canyon came to be, and why mountains around the world can provide a metaphor for human existence.

Let Sigrid tell you about the solar system that resolves around the Sun, including the order and characteristics of the planets within it. What is the closest planet to the Sun? What are the smallest and largest planets?

What happened when Expedition PROTECT and American Promise arrived at Jeffrey's Ledge, a marine protected area in the Gulf of Maine? The crew tells us about what they are doing and why.

Young black bears need to be careful when encountering the North American porcupine. Enjoy more footage from Alaska and Princess Royal Island in British Columbia, where young raccoons are also out and about.

Fracking is a controversial topic. This animated video tries to take a neutral look at fracking. It is relevant for all of us, because of high prices for energy and the danger to our drinking water.

Have you ever wondered what an escalator looks like on the inside, or how it works? Here's a brief demonstration.