Step inside the largest and most efficient automated delivery system on the planet. More than a courier, UPS is an epic transport network.

15 million years ago a hungry land animal sought out a new source of food in the water, starting a spectacular evolutionary journey so that today it looks like a fish. How did a creature built for land become master of the ocean?

From small viscous meat eaters to vegetarian giants, dinosaurs came in all shapes and sizes. Remarkable new evidence suggests that one dinosaur did not become extinct but evolved into a new animal species we all know today.

Experts unravel the mystery of the Dead Sea Scrolls and explore theories about their creation, including the Church's 50-year embargo on their publication.

What does it take to sink a destroyer in a naval battle today* How far will a team of engineers, naval weapons, and ship salvage experts have to go to get success in, Sinking of Destroyer?

What does it take to sink a destroyer in a naval battle today? How far will a team of engineers, naval weapons, and ship salvage experts have to go to get success in, Sinking of Destroyer?

The Apache is perhaps the most lethal attack helicopter in the world. Pass through the security protocols at the Boeing plant in Mesa Arizona, to see how this battle tank of the air is built. How it is engineered to be a stealth fighter, flying low over the battlefield resistant to heavy groundfire. Built to take multiple hits yet bring its pilots home. How it is engineered to hide its tracks as it steals through the skies, to evade enemy radar and heat-seeking missiles. How it sports some of the most sophisticated military technology on the planet. Workers at the Boeing plant, and the men who actually fight the battles and return home in the Apache, reveal the secrets of this deadly fighting machine.

The Apache is perhaps the most lethal attack helicopter in the world. Pass through the security protocols at the Boeing plant in Mesa Arizona, to see how this battle tank of the air is built. How it is engineered to be a stealth fighter, flying low over the battlefield resistant to heavy groundfire. Built to take multiple hits yet bring its pilots home. How it is engineered to hide its tracks as it steals through the skies, to evade enemy radar and heat-seeking missiles. How it sports some of the most sophisticated military technology on the planet. Workers at the Boeing plant, and the men who actually fight the battles and return home in the Apache, reveal the secrets of this deadly fighting machine.

Summer is the season of long, hot days spent lounging on a beach or splashing in the waves. It's associated with relaxation and fun, but, in fact, there's a lot of science behind the icons of summertime. National Geographic's "The Science of Summer" explores the mysteries behind the planet's most sweltering season and reveals the fascinating facts that make summer unique. School may be out but that doesn't mean the learning is over; National Geographic's "Science of Summer" explains why millions of people call summer their favorite time of the year.

It's one of the world's most famous natural wonders, yet little is known about its formation. Unearth its secrets, and relive the first expedition to its floor.

Of the five years he spends circling the world on the H.M.S. Beagle, Darwin spends a mere five weeks in the Galapagos islands and, contrary to conventional belief, his greatest epiphanies do not occur on the famed islands. Instead, they are a cultivation of years exploring the wilds of South America where forests become the cathedral of Darwin's religion. Darwin's senses are overwhelmed by a world teeming with life, but what he finds along the way is perplexing to a 19th century naturalist. He questions why the fossils he discovers look like giant versions of the sloths and armadillos still living nearby; why do the penguins and other birds he sees use their wings as flippers, fins, or sails - but not for flying; how could sea shells be found embedded in rock layers more than 100 miles from the sea? It is not until after he leaves the Galapagos - where mockingbirds, not finches capture his attention - that he is able to fully appreciate everything he has encountered and pull together his masterwork: On The Origin of Species.

Earthquakes, one of the most unpredictable and destructive forces in nature, can transform a busy city into a scene of devastation in a few seconds. As the number of cities grows, so do the potential casualties.