The space suits used by the astronauts on Gemini 7, known as grasshopper suits, were designed for comfort. But after two weeks inside them, that was the last thing on the crew’s minds.

There's a Limit to the Comfort Level of NASA Space Suits (3:32)

It's a partnership that's as unlikely as any: herds of bison on the move are kicking up chunks of earth. This, in turn, gives cliff swallows the valuable mud pellets they need to build their nests.

How Bison Are Helping Cliff Swallows Build Their Nests (3:38)

Greg Spriggs and Jim Moye are on a mission: to declassify all valuable film footage that exists of every U.S. nuclear test ever conducted.

Bringing Classified Nuclear Test Footage to the Public (1:47)

A flock of Andean condors have spotted a carcass in the Southern Cordillera region of Patagonia. It's a rare feeding opportunity in this barren land - and there will be a spirited competition for scraps.

These Condors Will Fight to Get a Seat at the Dinner Table (2:02)

The name sounds innocuous, maybe even charming. But it’s also known by another name—the ant lion—and it’s every bit as predatory and remorseless as that name sounds.

Doodlebug Is a Misleading Name for an Accomplished Assassin (3:04)

When birds need sleep, they do it on the fly--quite literally. They're able to enter a special kind of half-sleep state that lets them rest midair, which is especially important if you're a migratory bird, like the Alpine swift, clocking thousands of miles at a time. Glide into the astounding world of avian sleep.

The Secret World of Animal Sleep: Asleep on the Wing (3:01)

No bird is more skilled at in-flight feeding than a hummingbird, thanks to their ability to hover in the air. But if it's rainy, these fantastic flyers have to be extremely careful not to get hurt.

Why Hummingbirds Don't Like Flying in Rainy Conditions (2:17)

A military-grade thermal camera lifts the lid on the night time excursions of hippos on dry land. Those consist of grazing on a staggering amount of grass, while keeping a watchful eye out for roaming lions.

The Secret and Busy Night Life of Adult Hippos (3:27)

A shy orangutan makes great strides by confidently securing her share of breakfast. But she’s not above sharing her bounty of turnips with another orangutan, whom she’s befriended.

A Shy Orangutan Shares Her Breakfast With a Friend (2:11)

Separated from the mainland, the babirusa pigs of Sulawesi have evolved in total isolation. This has resulted in some pretty dramatic differences from regular pigs—especially in their appearance

Meet the Strangest Pigs in the World (3:14)

A herd of migrating elephants are acquiring necessary minerals like calcium and potassium from a burnt wood clearing. It’s also an impromptu reunion spot for all traveling elephant herds.

This Salt Lick Doubles as a Reunion Spot for Elephants (2:23)

In primates, recognition of snakes is instinctive, but fear of snakes is learned. Today, caretakers of the jungle school set about teaching them.

Orangutans Need to Learn to Fear Snakes (2:41)

The dominant bear in the swamp is fending off another challenge to his authority by an intruder. It's a clash of titans with mating rights on the line.

Stunning Footage of Two Bears Duking It Out for Dominance (2:40)

As spring begins, the surviving bees in the hive pick up their first task of the new year: dumping the corpses of the bees that died over winter.

The First Job Bees Have in Spring Is Grim (2:06)

The smart tool gives users step-by-step instructions based on WHO’s handwashing protocol

This ‘Health Mirror’ Teaches Proper Handwashing (1:30)

A trio of teenage lions are desperate to cross the shallows of the Luangwa River, in order to reunite with their pride. One problem: The river is infested with crocodiles, waiting for an easy meal.

Young Lions Try to Cross Crocodile-Infested Waters (3:42)

In 1799, Alexander von Humboldt set foot in the jungles of Cumana, in present-day Venezuela. What ensued was a detailed scientific mission to learn more about the natural world.

Humboldt's Journey to Cumana Was Packed With Discovery (3:21)

Alexander von Humboldt was intrigued by deadly electric eels. He was so determined to learn more about them, that in Los Llanos, he’d hold them in his hands to test the strength of their shock.

This German Explorer Held Electric Eels in His Bare Hands (2:05)

A female leopard is risking life and limb by trying to steal food from another male leopard. One wrong move and the male, a third bigger than she is, could make her pay.

A Leopard Risks Her Life to Steal Food (3:39)

See how researchers at Smithsonian's National Zoo are trying to glean insight into elephant foraging behavior and more.

How Smithsonian Researchers Are Studying Elephant Behavior (0:47)

One common misconception about the eruption of Vesuvius is that it happened suddenly and was over in an instant. But some experts suggest the events could have taken as long as seven hours.

The Vesuvius Eruption May Have Been a Gradual Process (3:08)

The Leopard Rocks—giant boulders spread out over hundreds of square miles—impress. But it’s the area's wildlife that really catches the eye: from leopards to peacocks to gray langurs.

The Wildlife at Leopard Rocks Is as Impressive as the Terrain (1:24)

In 1963, an Iceland volcano by the name of Surtsey began an eruption that would last for four years. To scientists, it’s become an invaluable opportunity to observe an environment closely resembling that of early Earth.

This Icelandic Volcano Recreates Early Conditions on Earth (3:42)

On the eve of the moon mission, NASA faced a protest by a group known as the Poor People’s Campaign. Their objection: $3 billion was spent on the Apollo mission, while poor people in the U.S. went hungry.

This Group Protested America's Bid to Put a Man on the Moon (2:11)

Edward Dwight Jr. was an ace combat pilot with a top aeronautics degree and 2,000 flying hours under his belt. In 1962, he was announced as a candidate to become America’s first black astronaut.

Ed Dwight Jr. Was Set to Become America’s First Black Astronaut (3:22)

At Kafue National Park, one cheetah has adapted his hunting strategy to find more prey: He hunts in the forest, instead of the open plains. This flexibility is good news for the future of Africa’s most endangered big cat.

A Cheetah Changes His Hunting Strategy in a Surprising Way (2:34)

A series of remarkably well-preserved human remains in a remote cave in Scotland has archaeologists grappling with a staggering question: were these bodies brought here during the Bronze Age to be mummified?

Was This Cave an Ancient Lab for Preserving Human Bodies? (2:56)

In July 1925, a young science teacher named John Scopes was in court, accused of contravening the Butler Act—a Tennessee law that prohibited the teaching of evolution in schools.

This Man Was Tried in Tennessee for Teaching Evolution (2:25)

Of all the herbivores of the Luangwa, warthogs are best equipped to deal with a drought: They’re natural born diggers, with snouts like trowels, that help them reach buried roots and dormant bulbs.

Warthogs Have the Tools to Survive in a Drought (2:02)

On March 10, 1933, a major earthquake caught the Los Angeles area by surprise. The devastation was of sufficient scale to spur scientific interest in earthquakes—and how to predict them.

Scientists Didn't Know Much About Earthquakes Before 1933 (3:18)