Pigs are preferred for xenografts because of their size and low disease risk

As part of the up to 15 pounds of seafood they consume daily, sea otters eat urchins that feed on kelp forests—sources of shelter and food to over 800 species—thereby making the marine mammal a keystone species.

The final shots of the Civil War were fired in the Arctic over 2 months after the South's surrender.

One of the most famous portraits ever taken is 'Afghan Girl' (1984) by Steve McCurry, yet the subject Sharbat Gula went much of her life without being identified or benefitting from the image's success.

One of the most famous portraits ever taken is "Afghan Girl" by Steve McCurry. Sharbat Gula, the subject of the photo, was not credited until 2002 for her role in the famous National Geographic cover, and continued to live in poverty after the photo was taken.

'Golden blood' is the rarest blood type in the world—fewer than 50 people are known to have it.

Watch footage from the moments the Titanic wreck was discovered by a joint US-French research team in 1985.

The Berlin Wall physically separated East and West Berlin for nearly three decades, preventing East Germans from fleeing to the West and earning the nickname 'the Iron Curtain.'

Peek into the love lives of thousands of strangers whom Stanford University researchers have been tracking since 2017 on this interactive page.

Pregnancy makes someone more attractive to the mosquito species that transmits malaria.

The world's largest waterfall is in the ocean and is more than three times the height of Angel Falls, the largest waterfall on land.

Watch a visualization of what it would look like to move along Earth's surface as fast as the International Space Station, or about 23 times the speed of sound.

In 1962, the US detonated a nuclear weapon in space, which produced an electromagnetic pulse that disabled three low Earth orbit satellites and damaged electrical equipment in Hawaii.

Hear 50 years of iconic hip-hop samples, the genre's foundational looped tracks.

The collapse of gas bubbles in the joint synovial fluid causes 'cracking' knuckles.

Watch Bruce Springsteen's 1985 performance of Woody Guthrie's 'This Land Is Your Land,' which he calls 'the greatest song ever written about America.'

Light takes approximately eight minutes to travel from the sun's surface to Earth, but it takes thousands of years to reach the star's surface from its core—a distance more than 200 times shorter.

Plato's famous allegory of the cave is a metaphor exploring the value of truth over ignorance.

Between 2002 and 2012, at least 12 people were killed in the Philippines in incidents related to off-key karaoke singing of Frank Sinatra's 'My Way.'

Rapid intensification is the increase in a hurricane's sustained wind speed by at least 35 miles per hour within 24 hours, which can strengthen it by up to two categories.

Metamorphosis evolved over millions of years as species that hatched as smaller versions of adults started exhibiting genetic mutations that differentiated juvenile and adult bodies.

Computer scientists first started trying to optimize dating using computers in the 1950s.

Although the moon passes between the sun and Earth each month, its orbit is tilted by five degrees, preventing Earth from experiencing a solar eclipse each month.

Watch the many different civilizations around the Mediterranean shift power from the year 2500 BCE to 0 BCE in this animated map.

Explore the 2025 Uber Lost & Found Index to find out the weirdest items that passengers left behind in Ubers last year, from ten live lobsters to a mannequin head with human hair.

Male pattern baldness accounts for more than 95% of hair loss in men and is characterized by thinning hair, hair loss, and a receding hairline.

The tallest tsunami in recorded history was 524 meters (1,720 feet) high—taller than the Empire State Building—and occurred in Lituya Bay, Alaska, in 1958 after an earthquake dislodged a rockface into the water.

Watch an animated visualization of how the Large Hadron Collider works, including how particles are accelerated through a series of machines and how collision data is collected and distributed worldwide.

Humans may have as many as 100,000 to 150,000 individual hairs on our scalps, growing at a rate of roughly 1 centimeter per month.

Explore how temperatures compare to historical averages in cities worldwide with this interactive global monitor.

The average banana produces one positron—the antimatter counterpart to an electron—every 75 minutes as its trace amounts of radioactive potassium decay.

Watch 4-plus decades of Pixar's opening logos.

George Lucas used Joseph Campbell's 'hero's journey,' a narrative structure that encompasses the common characteristics of multiple cultures' mythologies, to revise 'Star Wars.'

Relax to a livestream of brown bears chilling in Katmai National Park in Alaska.

Watch President John F. Kennedy's speech on going to the moon

Explore Lewis and Clark's 8,000-mile journey in Google Earth.

Examine this captivating animation 'building' a human—illustrating the roughly 40 weeks of fetal development.

If a source of music traveled past someone at twice the speed of sound, assuming sufficiently sensitive hearing and powerful equipment, they would hear the music backward.

The US jobs projected to shrink the fastest over the next decade include typists and word processors.

The Aztec Empire ruled over 80,000 square miles of central Mexico for nearly a century—until a small band of Spanish conquistadors brought it down in 1521.

Explore a collection of famous literary maps, including original images from 'Treasure Island,' 'The Swiss Family Robinson, ' and 'Walden.'

Explore an interactive timeline of Earth's 4.5-billion-year history to visualize shifting landmasses and oceans, view the locations of significant asteroid impacts, and learn about major geological and biological events.