largest known canyon in the solar system — is still tectonically active even though the Red Planet is geologically "dead," new research on a previously record-breaking marsquake reveals.

On Aug. 25, 2021, NASA's InSight lander, which touched down on the Red Planet in 2018, detected a powerful marsquake, designated S0976a. The Martian equivalent of an earthquake reached magnitude 4.2, which, at the time, was the most powerful quake that InSight or any other Mars lander had ever seen. (Since then, a 4.7 magnitude marsquake in May 2022 knocked it off the top spot, but S0976a remains second on this list.)

Unlike most marsquakes, which have been minor tremors triggered by meteorite impacts near InSight, S0976a was a deep rumble that originated from the opposite side of Mars as the robotic seismologist, in the western half of Valles Marineris.

In the new study, published Oct. 15 in the journal Nature Communications, researchers reanalyzed the seismic wave data of S0976a and found that the quake originated from within a fault line running below the enormous canyon. The most likely explanation, they argue, is that there was tectonic movement in this hidden crustal crack.

"Valles Marineris is one of the most spectacular geological structures anywhere in the solar system, but until now we didn't know for certain that its faults are still active," study first author Jung-Hun Song, a researcher in the Department of Earth Science and Engineering at Imperial College London, said in a statement. "What we see is that this is not just a 'dead' fossil landscape, as faults deep beneath the canyon can still slip and generate marsquakes, long after the geological processes that originally formed them have ceased."

A geologically "dead" world

Valles Marineris is an enormous set of interconnected gullies and ravines stretching up to 2,500 miles (4,000 kilometers) in length, or roughly 10 times longer than the Grand Canyon. It is also up to 20 times wider and five times deeper, meaning that if you found yourself stranded at the bottom, it could take you a couple of months to climb out again.

The enormous chasm — named after the Mariner 9 spacecraft, which helped discover it in 1971 — is clearly visible from space, like a giant scar carved into the Red Planet's face. From orbit, you would also see the nearby Tharsis region, which is home to Mars' giant volcanoes, including Olympus Mons, which is at least three times taller than Mount Everest.

These imposing structures are proof that Mars was once geologically active, perhaps even more so than Earth. However, scientists think the Red Planet's surface has remained relatively unchanged for nearly 3 billion years, according to the European Space Agency.

The reason for this is twofold. First, Mars is smaller than Earth, so its core and mantle have cooled much faster than our planet's and are, therefore, less dynamic. Second, Mars has no tectonic plates. Instead of giant patches of crust butting against each other, the Red Planet's outermost layer is almost completely intact and acts like a giant lid over its cooling molten innards. (Research published earlier this week throws the "dead" theory into question, hinting that magma may still lurk below dormant Martian volcanoes).

Despite this, Mars still has fault lines. But rather than being a boundary between tectonic plates, these lines are more like giant cracks in its crust, some of which are visible at the surface.

Signs of tectonic life

In the new study, researchers discovered proof of what they call a slip-strike marsquake, where "blocks of crust move horizontally past one another along a steep, deeply rooted fault," the team said. They believe this occurred somewhere between 12 and 25 miles (20 to 40 km) below Valles Marineris.

The researchers also simulated several other potential causes of the marsquake, including a major asteroid strike or a landslide within the canyon, but nothing else could explain the patterns they saw.

"What makes the result compelling is that several completely different types of evidence point in the same direction," Song said.

The finding also raises hopes that similar tectonic activity could one day be detected on other worlds across the solar system.

"Our study opens up exciting possibilities for discovering ongoing seismic activity on other planetary bodies that we might otherwise consider geologically inactive," Song said.

Mapping Martian vibrations

The discovery highlights the importance of detecting and studying marsquakes, which were only officially discovered in 2019, thanks to InSight. (Scientists have since uncovered older marsquakes, using data collected by the Viking landers in the late 1970s.)

"S0976a has turned out to be an extraordinary event," study co-author Doyeon Kim, head of Imperial College London's Terrestrial and Planetary Seismology Lab, said in the statement. "Its waves traveled through the core and helped us investigate the deepest part of Mars, and now they are telling us what happened at the source itself. From a single marsquake, we can learn both about the center of the planet and about an active fault beneath one of its most remarkable landscapes."

Scientists have similarly used marsquake vibrations from InSight to map out Mars' interior, leading to several intriguing subsurface discoveries, including dozens of blobs left over from ancient protoplanets, the hidden cause of the planet's uneven hemispheres, a potentially active "mantle plume" and a gigantic underground water reservoir containing enough liquid to cover Mars with a mile-deep (1.6 km) ocean.

Unfortunately, in December 2022, InSight quite literally bit the dust: A thick covering of Martian powder blocked its solar panels, preventing the lander from returning signals to Earth and thus ending its mission.

This means we currently have no way of detecting new marsquakes. However, the new study proves that the lander's archived data can still lead to exciting discoveries.

Mars quiz: Is your knowledge of the Red Planet out of this world?

'> Gigantic chasm on Mars is still tectonically active wrote that the Scythian nomads inhaled the fumes from burning hemp seeds. And evidence of cannabis use was previously discovered in a cemetery in China dated to about 500 B.C. The new study, however, pushes back this date by three centuries.

Researchers discovered more than 1,000 whole cannabis seeds and around 500 partial seeds in the Tunnug burial mound, and they carbon-dated them to between 800 and 760 B.C. They also recovered several human hair samples from the grave. An analysis of the hair revealed signals matching cannabinol and THC (tetrahydrocannabinol), psychoactive chemical compounds found in cannabis. The tests could not determine how much of the drug people consumed, however.

"The molecular traces in the hair and the cannabis seeds come from the same grave and suggest that cannabis was used for its intoxicating properties," study first author Gino Caspari, an archaeologist at the Max Planck Institute of Geoanthropology in Jena, Germany, said in a statement.

But given the burial context of the discovery, the use of cannabis may have had a darker purpose.

"In this princely tomb, the burials were accompanied by extensive horse sacrifices and, most likely, human sacrifices as well," Caspari said. The tradition of human sacrifice, in particular, "would have potentially made the plant a useful agent to calm individuals who were to be included in the rituals," the researchers wrote in the study.

The new study confirms the ancient use of cannabis in funerals in Central Asia and extends the date back to 2,800 years ago, the researchers noted. Future work is planned but will focus on other aspects of ancient cannabis.

"We have already begun sequencing some of the plant samples," Caspari said. "This will help us learn more about the history of the domestication and spread of the crop soon."

'> 2,800-year-old tomb in Siberia has evidence of the earliest use of cannabis — possibly as a way to calm human sacrifice victims

Between 1996 and 2017, metal detectorist Peter Hughes found the lock and much of the hoard, which included gold and silver coins. The lock was subsequently acquired by Amgueddfa Cymru — National Museum Wales, which worked with researchers at Cardiff University in Wales to decipher its combination.

To study the lock's internal mechanisms, the team used micro-CT scans, which make thousands of X-rays that can then be configured into a 3D digital image. By matching internal notches to external letters in the digital 3D image, the researchers were able to decipher the correct four-letter code — "ANCE" — and open the lock.

"We normally use this technology to study bones and other biological structures, so investigating a 400-year-old padlock was certainly a first for us," David Williams, a research associate at the Musculoskeletal Biomechanics Research Facility at Cardiff University, said in a statement. "It's not every day you get to solve a 400-year-old mystery!"

Smugglers' ship

The Ann Francis was owned by Francis Shaxton, a merchant and notorious smuggler. Francis claimed the ship was sailing along the eastern English coast from King’s Lynn to Hartlepool, when it was actually traveling in the opposite direction, heading to Spain to deliver a cargo of wheat. Spain was dependent on grain shipments at the time and paid for such shipments in gold and silver from colonial conquests in Central and South America, according to Amgueddfa Cymru.

The ship was traveling back from Spain to England when, on the evening of Dec. 28, 1583, it was caught in a violent storm. After heading off course, the ship ended its journey in ruin off Margam beach.

A parish register noted the loss of 14 sailors during the same month as the wreckage, which could have been The Ann Francis's crew, according to Amgueddfa Cymru. The deaths were blamed on the nefarious work of a supposed witch.

Locals were quick to loot the Ann Francis wreck before a legal dispute ensued over who had the right to its goods. One Welsh lord claiming the wreck made an inventory list of items he impounded, which included cannons, guns, a piece of mast, Spanish silver and three chests with their locks broken. The newly cracked lock could have originally secured one of these chests, according to Amgueddfa Cymru.

Centuries after the ship was wrecked, Hughes found the lock near a previously undiscovered stash of Spanish silver coins and coin weights while metal detecting on the beach.

"When I found the lock I was immediately astonished by the incredible workmanship and its astonishing condition," Hughes said. "When I moved the ring dials of the combination they turned with ease after over 400 years beneath the sands and I was left in disbelief."

Hughes said he attempted to open the lock himself over many years but could never find the right combination. After Amgueddfa Cymru acquired the lock, staff were concerned that they could hear grit moving around inside the dials, and with more than 1,000 possible combinations, they didn't want to cause any damage.

The micro-CT scans offered a nondestructive view inside the lock, and an opportunity to finally identify the correct four-letter combination.

"Elizabethan combination locks are known in Britain, but this one is in exceptionally good condition and is associated with a dated wreck, making it a unique find and the code a tantalising mystery to solve," Alastair Willis, the senior curator for numismatics and the Welsh economy at Amgueddfa Cymru, said in the statement. "Of course, now we've solved it, we are left wondering if the code meant something to its owner."

'> Cryptic padlock from a 400-year-old shipwreck finally opened ‪—‬ but it leaves a mystery Mycobacterium leprae, which causes leprosy.

This strain of leprosy has never been seen in this part of Europe before, which hints that the individual had traveled and interacted with people from across the Roman world. The man was buried in a wooden boat surrounded by unusual objects, indicating he was a high-status person, according to a research study.

"The results were particularly striking in the case of one individual," study co-author Ben Krause-Kyora, an archaeologist at the Institute of Clinical Molecular Biology (IKMB) at Kiel University in Germany, said in a Nov. 3 statement. "He could, for example, have been a mercenary in the Roman army who later settled between the Elbe and the Weser [rivers]."

In the study, published online Oct. 15 in the journal iScience, Krause-Kyora and colleagues analyzed the genomes of people buried at the coastal settlement of Fallward. The settlement originated in the first century B.C. but gradually declined and became a cemetery by the fifth century A.D. Among the 200 cremation burials and 60 inhumation burials originally excavated in the 1990s was a distinctive grave made from a wooden boat.

The oak boat was over 13 feet (4 meters) long and sealed with a roof-like structure, the researchers said. It held the skeleton of a man who was about 50 years old when he died some time between A.D. 425 and 450. His grave goods included a small box shaped like a water bird, an ornate chair or throne carved out of alder wood, a bronze basin and a maple stool with a hunting scene and a runic inscription. The maritime artifacts coupled with the man's well-developed upper arm bones suggest he may have worked as a fisherman or boatman just before he died, the researchers wrote.

"The grave goods placed in the tomb aroused particular scientific interest," study co-author Hauke Jöns, an archaeologist at the Lower Saxony Institute for Historical Coastal Research, said in the statement. "The man possessed a late Roman military belt, which suggested that the deceased had had connections across great distances."

A rare form of leprosy

To learn more about this unusual burial and to determine where the man was from, researchers analyzed his DNA.

"Genetic analyses confirm that a man buried at Fallward originated from the Danube region," study first author Daniel Myburgh, an ancient DNA researcher at IKMB, said in the statement. "He was also infected with a very rare leprosy pathogen."

The researchers found the DNA of the bacterium M. leprae in one of the man's teeth and in a foot bone. Because the leprosy DNA was so well preserved, the researchers were able to narrow down the strain that had infected him. This strain of leprosy may have evolved in Egypt around the fourth to second centuries B.C. and had never before been found in Central or Northern Europe, according to the statement.

But the man showed no signs of leprosy lesions in his skeleton, the researchers said. Leprosy first attacks the nerves and skin, but it can eventually eat away at the bones of the skeleton, particularly affecting the nose, jaw, hands and feet.

"Leprosy is a chronic disease," study co-author Almut Nebel, a biologist at IKMB, said in the statement. "Either he was affected by an asymptomatic form of the disease, or the disease had so far only affected soft tissues. He may have travelled long distances whilst carrying the disease."

While the researchers don't know exactly what happened in this man's life, they suggested he might have been a mercenary who served in the Roman army and later retired to northwest Germany, becoming a high-status member of the community who was honored with an alder-wood "throne" in his burial. But he also may have acquired the Roman belt through trade, inheritance or as a war trophy, the researchers wrote.

Either way, the man's skeleton and his grave goods suggest that northwest Germany had long-distance connections in Europe even after the fall of the Roman Empire, according to the statement.

What do you know about the bones in your body? Test your knowledge with our human skeleton quiz.

'> 1,600-year-old burial holds remains of man infected with a 'very rare' strain of leprosy in Germany Cecily Costello, a research wildlife biologist at Montana's Department of Fish, Wildlife and Parks, told Live Science. "It is easy to imagine the difficulty this grizzly bear experienced trying to reach the other side," Costello said.

This past May, another grizzly wasn't so lucky. Braving a crossing near one of Lingenpolter's attempts, the 27-year-old male bear was struck and killed by a truck, triggering a multicar rollover.

It's crucial for grizzly bears (Ursus arctos), also known as brown bears, to have room to roam. When they can't move between populations to mate, small groups get genetically isolated. And what's true for bears can also be true for other wildlife. "It's really challenging to be a small, fragmented population," said Michael Proctor, a wildlife biologist at Birchdale Ecological Ltd., a Canada-based environmental consulting firm. Such fragmentation is "one of the mechanisms by which we lose entire communities, and sometimes whole species," he told Live Science.

Nowhere is this challenge more urgent than in the 2,100 mile long (3,400 kilometers) region stretching along the spine of the Rocky Mountains between Yellowstone in Wyoming and the Yukon in northern Canada. The area, which spans five U.S. states, two Canadian provinces, and more than 75 Indigenous territories "represents the most intact, connected, wild, large mountain region in the world," Jordan Reeves, program director of landscape connectivity at the Yellowstone to Yukon Conservation Initiative (Y2Y), which aims to secure connectivity throughout the region told Live Science.

But as highways, rail lines, and human development fragment its valleys, maintaining connected pathways for grizzly bears across this landscape has become a challenge.

Grizzlies range across vast, diverse terrain, spanning high-elevation alpine habitats, mid-mountain slopes, and low valley bottoms, which means safeguarding their movement can also protect passageways for coexisting species, including wolverines, mountain goats, elk and bighorn sheep, Proctor said. That's why researchers are trying to understand why, where and when grizzlies move. And what stops them in their tracks.

"We're looking at how a bear sees the world," Andrew Derocher, a bear biologist at the University of Alberta who has used GPS collars on grizzly bears to trace their movements, told Live Science.

Nature versus nurture

When Sarah Sells started her graduate studies in animal behavior, her supervisor told her to "try to crawl into their fur brains and understand how they think," Sells told Live Science. Although we can't recreate exactly what's going on between a grizzly's ears, GPS collars that track animal movement hourly can tell scientists a lot about how animals behave, said Sells, who is currently the assistant unit leader of the U.S. Geological Survey's Montana Cooperative Wildlife Research Unit.

That tracking data is starting to produce an incredibly detailed picture not just of where bears go but also how and why they're making those choices.

"Bears are food finding machines," Chris Servheen, a bear biologist with the International Union for Conservation of Nature's Bear Specialist Group, told Live Science. "So remembering where they found food is critical to their success in life."

Using a combination of telemetry data (information collected by tracking devices) and movement modeling, Derocher and colleagues have investigated how well grizzlies remember where food is and when it is best to visit a foraging patch. Derocher's research showed that about two-thirds of the bears have a great memory for where and in what season they previously found food. His tracking data also revealed that wild bears generally avoid humans. But bears have only a few months to fatten up for winter. If food is scarce, many bears go into human environments and sometimes get killed, Proctor said.

The data is also offering insight into different bear "personalities." Bears are ultimately individuals, with their own traits and quirks, Servheen said.

Tracking data suggests that a lot of bear behavior is transmitted culturally via a mother's influence. Sometimes, the wrong behavior can get passed down to the next generation, Servheen said. For example, an infamous female grizzly known as 399 jaywalked potentially hundreds of times in the Jackson Hole valley in Wyoming while managing to keep her distance from humans. Her 20-odd cubs learned to follow her example, but they lacked her strategic caution. Several were killed by vehicles or management euthanizations.

"It's a risky thing to teach your kids to do stuff like that," Servheen said. "And her offspring weren't as smart as she was."

A cracked windshield

Further north along the region between Yellowstone and the Yukon, Proctor's first DNA survey across 1,500 square miles (4,000 square kilometers) of southern British Columbia in the late 1990s shattered his illusion that the bears, along with bighorn sheep (Ovis canadensis) and other species in this province, were free to roam. Instead, he found a "cracked windshield" landscape, where roads and human sprawl had fractured the wilderness into isolated genetic islands. In the 2000s, the genetic diversity of the South Selkirk grizzly bears — a detatched subpopulation inhabiting southeastern British Columbia, northern Idaho, and northeastern Washington — was so low, for example, that biologists feared the bears wouldn't survive.

But Proctor and his colleagues went on to use bear movement data to model pathways through human-settled valleys. Proctor was so convinced about the viability of one potential corridor that he paid 10,000 Canadian dollars ($7,000) of his own money to buy a key piece of land right in the middle of it. "That was the first canoe over the waterfall of purchasing connectivity land," Proctor said

Proctor’s land secured a segment of a crucial connectivity corridor and, in the following years, he and other scientists partnered with trusts to purchase other land parcels, build fences, and establish safe corridors for grizzlies in the Creston Valley in southeastern British Columbia. These actions helped bears move north and south (sometimes across the border) and between the South Selkirk Mountains and Purcell Mountains. The researchers then watched bears like "Captain Hook," who'd been shot in the leg, hobble into the South Selkirks and breed with eight females. By 2021, nine immigrant bears had produced 27 new offspring within the population.

"This is gene flow; this is connectivity," Proctor said. "We took a completely isolated population and pretty much recovered it."

Despite efforts to safeguard corridors through human occupied landscape, roads continue to stop bears in their tracks. When Servheen tracked bears near Highway 2 in northwest Montana, he found that many of the grizzlies avoided the highway altogether and those that crossed did so at night. But he also found that the bears' crossings clustered in specific sections of the road. Finding the crossing zones has helped researchers identify good locations for constructing overpasses and underpasses on many busy highways, but a crossing structure on its own is not enough, Servheen cautioned.

A bear's memory for where to find food is exemplary, but there's no special reward in a bear's brain for crossing a road safely — only a fatal penalty when they don't, Servheen said. So conservationists can't rely on bears to remember where crossings are. Instead, they must build fencing along the highway to funnel wildlife into the underpasses or overpasses. Then, the immediate land on each side needs to allow animals safe passage. "Otherwise, you have a bridge to nowhere," Servheen said.

Now researchers such as Sells are trying to use data about bears' likeliest routes to determine potential corridors in locations where they have little tracking data or where few bears live yet.

To do this, Sells is developing a virtual "Sims for Bears" that recreates the Continental Divide Ecosystem in Montana. In the life-simulation video game "The Sims," players give virtual humans personality traits, preferences and needs, and then drop them into a virtual environment to see how they behave.

Sells built the model using the GPS collaring data from 65 grizzly bears navigating individual paths through greenery, riparian areas and around forests and roads. Then, she "parachutes" an individual digital bear into a detailed computer simulation of real-world terrain and has them take thousands of virtual steps. By running these multiple simulated bears through thousands of iterations across the digital terrain, the researchers can watch where the virtual bears repeatedly choose to walk, effectively creating a map of predicted movement corridors.

Sells has used the model to predict how grizzly bears might recolonize the Bitterroot ecosystem of Idaho and Montana, which Lingenpolter was heading toward when attempting to cross Interstate 90.

To get to the Bitterroot Mountains, bears must pass through a valley filled with people, roads, garbage and fruit trees. "So knowing where they are more likely to end up is helpful to address things that could be difficult for humans or bears," Sells told Live Science.

The people problem

The data is also confirming that the greatest barrier bears face comes from human contact or transportation infrastructure across the entire Yellowstone-to-Yukon region. Studies from across west-central North America report that humans directly or indirectly caused between 77% and 90% of grizzly bear deaths from 1989 to 2015. Hunting, managed kills in urban areas and road and rail collisions all take a toll.

Bears in the wild usually avoid people, but some bears seek out human-dominated areas because they know these places are a source of food. People move to the Elk Valley in southeastern British Columbia because they love nature, but then they plant apple trees in their backyard, which attract bears, said Clayton Lamb, a wildlife scientist at the nonprofit Biodiversity Pathways.

Quickly, a bear eating backyard apples gets labeled a "problem bear," "when really it is a 'people problem,'" Lamb told Live Science.

Even human recreation takes a toll on bears' health and ability to move freely. Lamb's research has shown that grizzly bears try to avoid areas next to busy cycling and hiking trails.

To minimize human-bear conflict, Michelle McLellan, a wildlife ecologist at Biodiversity Pathways, has tracked trail use by both people and grizzlies in the West Kootenay region of British Columbia. McLellan documented people's habits using trail cameras and apps such as Strava Metro. Her research shows that the bears use the trails to move quickly between foraging spots but have learned not to use the trails that are most popular with humans. Consequently, the Nelson Cycling Club decided to close certain trails in the spring and cautioned riders about when and how to use the open trails. "Ride aware, make noise, slow down when needed," the club cautioned in its May newsletter.

Working with information from McLellan, the club has cut back overgrown vegetation along sight lines to prevent mountain bikers from startling bears at close range. They've also constructed wooden platforms on sections of trails that clatter and rumble as bikes pass over them, giving bears early notice of approaching riders. "The key is to not surprise them by making a lot of noise." McLellan told Live Science, noting that grizzlies are more likely to attack if they are surprised.

One advantage of having human mountain biking and hiking trails concentrated close to towns is that it focuses recreation into specific areas, Lamb said. Keeping trails condensed supplies multiple accessible paths and reduces humans encroaching on true wilderness — prime bear habitat. "The goal would be to ensure that there's sufficient recreation opportunities for people to stay healthy and connected to their local landscape while ensuring that wildlife can still move around and access their habitats," Lamb said

Learning to share

As humans increasingly live, work and play in bear territory, it's important to recognize the impact on the animals, Servheen said. "The bears never get a day off," he said. "Every day, they're trying to stay away from people and make a living in a place with multiple people on the landscape."

Bears expend a lot of much-needed energy trying to avoid people, and they won't be able to do that forever, Servheen said. As humans increase the development of private lands and recreation in bear territory, the squeeze is on. "There's going to be more conflicts with bears, and more dead bears," Servheen said.

The bears have done their part, Lamb said. His research has shown that bears living near humans are adapting by becoming mostly nocturnal, which reduces their odds of clashing with humans. "So, we need to meet them where they are at and see what we can do to share the space," Lamb said.

On the human side, people need to make it less tempting for bears to be in human dominated areas, McLellan said. That means keeping garbage stowed and making sure there is no ripe fruit available. "If you live rurally, you want them to be able to pass through your property but not linger near your home or in your front yard," McLellan said.

Bears have proved to be adaptable and persistent; Lingenpolter tried to cross the highway dozens of times before finding a way under. However, Servheen warned that we are putting them in a tough spot. To keep bear populations stable, scientists need data on bear behavior to help inform land management policies that create safe pathways for grizzlies to move through human dominated areas and regulate recreation with bears in mind, Servheen said.

"If we want to have bears in the future, we need to think about the needs bears have for some level of space on the landscape," Servheen said.

Securing that space across the vast Yellowstone to Yukon landscape requires more than just land acquisitions and highway overpasses — it requires increasing public awareness and counteracting the perception that bears are inherently aggressive and irrational, Proctor said. If people understand bear behavior, they can learn to act in ways that neither attract bears nor threaten them. And understanding the totality of bears’ strong drive to survive, and protect each other, can elicit empathy and motivation to protect this iconic species.

Early in his career, Proctor captured, immobilized and radio-collared a mother grizzly with her two yearlings, or newly adolescent bears. While the research team worked, the young bears circled quietly at a distance. When the scientists finally stepped back and the mother began to stir, the yearlings approached cautiously. As the mother's groggy head rested on a log, the yearlings' long-clawed front paws delicately explored the radio collar. Then, each one rested its head directly on hers, to form a quiet pile of three bear heads.

"They just wanted to touch mom after this ordeal," Proctor said. "Yes, grizzlies can be rough and dangerous but they can also be gentle at times," Proctor said.

Reporting and travel for this story was supported by the Sitka Foundation and the Science Media Centre of Canada.

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'> 'We’re looking at how a bear sees the world': From forest trails to 'Sims for Bears,' researchers are learning how grizzlies navigate a fragmented...