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Some chapters in human history are more important to relive than others.
The Battle of Waterloo ended a war that had lasted 23 years, but on 18 June 1815, thousands of people died when the allied armies led by the Duke of Wellington and Gebhard Leberecht von Blücher defeated Napoleon Bonaparte and his forces south of Brussels.
Paintings, books and eyewitness accounts have preserved details of the conflict more than two centuries later. Until recently, only two complete skeletons had been found from the battle, leaving gaps in the grim story of the horrors that unfolded during and after the clash.
Archaeologists and war veterans have found remains of amputated limbs and horses at the site, which help tell the story of what happened after the battle.
But other chapters, such as those describing the loss of our ancestors, become harder to figure out as time passes. A chance discovery of bones in a cave reveals clues to a much older tragic mystery.
We are family
Five teeth found in 2015 in a rock in France's Rhône Valley could explain why Neanderthals disappeared from the face of the Earth 40,000 years ago.
The once-in-a-lifetime find, nicknamed Thorin after a character in "The Hobbit," has puzzled researchers for nearly a decade. While genetics suggested the Neanderthal was 105,000 years old, archaeological context indicated he lived 40,000 to 50,000 years ago.
New research has revealed that Thorin belonged to a Neanderthal lineage that was isolated from other groups that lived nearby for an unexpected 50,000 years, making his DNA appear older than it was.
This isolation put Neanderthals at an evolutionary disadvantage and may have led to their demise.
Fantastic creatures
When scientists observed dark sleeper fish eating young Japanese eels, some of the eels were able to escape through the predators' gills within minutes.
To get a peek inside, researchers used an X-ray camera and observed the eels freeing themselves from the fish's stomach.
"Before we made the first X-ray images, we never thought that eels could escape from the stomach of a predatory fish," said Yuha Hasegawa, an assistant professor at Japan's Nagasaki University.
"It was truly amazing for us to witness the desperate escape of the eels from the predator's stomach to the gills."
About the universe
Colorful northern lights above New Zealand's mountains, the glittering Dolphin Head nebula and a sunny silhouette of the International Space Station are just some of the winners of the Astronomy Photographer of the Year competition.
The eventual winner of the contest was photographer Ryan Imperio for his photo taken during the October 2023 annular solar eclipse.
The image captured the progression of Baily's beads. The phenomenon is visible for brief moments during an eclipse when sunlight shines through the moon's valleys and craters, creating glowing droplets of light.
Additionally, SpaceX's Polaris Dawn crew made history this week by completing the first commercial spacewalk and setting other space exploration records ahead of their expected return in the coming days.
Power of nature
The world's most devastating mass extinction event wiped out more than 90 percent of all life on the planet about 252 million years ago. Now scientists think they've discovered a climate phenomenon that played a crucial role.
Previously, scientists thought that carbon dioxide released by volcanic activity caused sudden global warming, acid rain and ocean acidification.
But an intense, prolonged El Niño that lasted for years and originated in an ancient body of water much larger than the present-day Pacific Ocean would have amplified the effects of the volcanic activity.
Together, these two phenomena may have caused the Great Dying, and the catastrophic extinctions began on land before they occurred in the ocean.
Long ago
Some scientists have long believed that the people of Rapa Nui suffered a devastating decline hundreds of years ago. Also known as Easter Island, it is known for its hundreds of carved stone statues.
But a new analysis of the ancient DNA of 15 former residents of the island who lived there over the past 400 years tells a different story.
Genetic analysis shows that the island's small population continued to grow until the 1860s, and that the island's inhabitants reached America in the 14th century, long before Christopher Columbus in 1492.
Meanwhile, the search for the origins of Stonehenge's mysterious central altar stone is heating up. Researchers have ruled out a seemingly likely ancient location as the source of the monolith.
Explorations
Take a closer look at these new findings:
- A breakthrough in physics brings scientists closer than ever to developing a nuclear clock that ticks so steadily that it won't lose a second of time, even if it lasts 1 billion years.
- Lab-grown cocoa and fermented fava beans could be used to create the guilt-free chocolate of the future, avoiding rising cocoa prices and the damaging effects of cocoa farms.
-Rare, recently discovered fossils have shown that some species of enormous, ancient flying reptiles called pterosaurs glided like vultures, while others had a different flying style.
- NASA astronaut Butch Wilmore believes he and his colleague Suni Williams could have returned to Earth aboard Boeing's Starliner capsule, which returned empty last week, "but we just ran out of time," he said.
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