Inventors

For six weeks, luna moth caterpillars gorge themselves on the leaves of the marula tree. Then, when they're ready, they instinctively weave giant cocoons around themselves in preparation for their stunning metamorphosis.

Timelapse Footage of a Giant Caterpillar Weaving Its Cocoon (2:34)

Free from their mother's care, five young lions must fend for, and feed, themselves. Their first challenge: a giant giraffe who refuses to be caught.

Incredible: Five Lions Take Down a Giraffe (2:49)

In 1992, Christopher McCandless set off to test if he could survive alone in the wilds of Alaska. It didn't go as planned.

What Happened to Chris McCandless? (3:38)

Green tree vipers can kill in the dark. With special heat-sensing abilities, they can find prey that's all but invisible.

A Pit Viper's Sixth Sense (2:03)