The Xiaomi Smart Band 9 seems, on first impressions, even better than its predecessor. It boasts up to 21 days of battery life, a brighter 1.62-inch AMOLED display and a more accurate heart rate sensor. Moreover, it features more in-depth sleep tracking features and a whopping 150 sports modes. The cherry on top? It costs only $63.

Xiaomi Smart Band 9 review

Xiaomi Smart Band 9: Design

• Ultra-light and discreet-looking
• Silicone straps may slip off the wrist during sleep
• Can be attached to a running clip (sold separately)

Design-wise, the Xiaomi Smart Band 9 does not stray far from its predecessors. Weighing just half an ounce (15.8 grams) and measuring only 0.85 inches (21.6 millimeters) in width, it is only slightly bigger than its younger siblings. We liked this exceptionally light and compact design. The Smart Band 9 never got in the way of our clothes or exercise equipment, and it felt like a much-needed change after all the bulky smartwatches we tested beforehand.

Following the tried and tested formula, this Xiaomi model also features straps that can be detached with a quick-release mechanism. This was a big plus point for us. The default silicone straps turned out to be somewhat unreliable in our tests: they felt flimsy and uncomfortable to wear for the most part, and on at least two separate occasions they slipped off our wrist during sleep. We were not fond of the band's dull pinkish color, either, and its silicone coating seemed to easily attract dirt.

Interestingly, the Xiaomi Smart Band 9 can also be inserted into a running clip. This little contraption allows you to attach the watch to your running shoe so you can track a range of performance metrics, from running cadence and stride length to ground contact time ratio — and it costs less than $12. For runners on a tight budget, this is a fabulous solution.

Xiaomi Smart Band 9: Display

• Bright, easy-to-read AMOLED display
• Relatively resilient to scuffs and scratches
• Plenty of watch faces to choose from

The Xiaomi Smart Band 9 has a relatively small 1.62-inch display, but we did not find it particularly difficult to navigate. Given our underwhelming experience with the display on the Smart Band 7, we were pleasantly surprised by how responsive and easy-to-read this one was, even when we tried to operate it with wet hands or under direct sunlight.

We also liked how it looked. The display in the Xiaomi Smart Band 9 is crisp and colorful and can be customized with over 200 different watch faces. And if that is not enough, you can even use photos from your gallery to put on your screen.

The display seemed surprisingly durable, too. The AMOLED glass did not scratch or scuff during our extensive testing, even though we must have accidentally bumped our watch at least a dozen times. It is refreshing to see such resilience in a fitness tracker costing less than $70.

Xiaomi Smart Band 9: Features

• Advanced health-tracking features
• Over 150 sports modes
• No built-in GPS tracking (it runs off the phone signal)

The Xiaomi Smart Band 9 impressed us with its robust health-tracking features. This humble-looking watch can track your steps, heart rate, oxygen saturation, sleep quality, stress levels, menstrual cycle and more, making it a surprisingly comprehensive tool for monitoring your energy levels and post-exercise recovery.

Speaking of exercise, the Xiaomi Smart Band 9 can track over 150 activities, from outdoor hiking and cycling to dance and weightlifting. We would not recommend it for competitive swimming or diving, though — it has only a 5ATM water resistance rating.

On the other hand, the Xiaomi Smart Band 9 does not have any major smartwatch features or built-in navigation tools like GPS. Sure, it can update you on the weather forecast or receive phone notifications, and it can use the phone's mobile signal to track your location, but that is pretty much it. The Smart Band 9 is nothing like the high-end Garmin models, but then its ultra-affordable price fully reflects that.

Xiaomi Smart Band 9: Performance

• Three weeks of battery life
• Patchy app connectivity
• Imprecise heart rate measurements during intense exercise

Performance is where the low price point of this watch shows. True, the Xiaomi Smart Band 9 easily lasts three weeks on a single charge — in fact, we managed to get nearly a month of battery life in our tests — but its app connectivity and tracking precision leave much to be desired.

The Xiaomi Smart Band 9 was slow to set up, and it took us several attempts to pair our watch with the Mi Fitness app. Once we managed to get everything up and running, we kept experiencing some minor yet annoying connectivity issues. On several occasions, the app did not record our workouts or sleep properly, and it often took considerable time to sync our devices.

We were also underwhelmed by the accuracy of the Smart Band 9’s heart rate sensor. During one workout, we wore our watch alongside a Polar H9 chest-strap heart rate monitor, and found significant discrepancies between the readings: during intense exercise, the heart rate values differed by as much as 20 beats per minute. In all fairness, these differences were far less pronounced at rest. Therefore we would not recommend the Xiaomi Smart band 9 for tracking lung-busting activities, but it could still do a relatively good job during sleep and low- to moderate-intensity workouts.

Xiaomi Smart Band 9: User reviews

Amazon's customer reviews gave the Xiaomi Smart Band 9 a 4.3 out of 5 stars rating, with nearly two-thirds of users giving it a full five stars. Positive reviews praised this fitness tracker for its long battery life, ease of use and good value for money. As one user said, "It's just as accurate (if not more so) than the Fitbit and colorful. The settings are easy to get to, and I'm pretty satisfied with the results and tracking for sleep."

Negative reviews often revolved around limited functionality and poor tracking accuracy. As one user commented, "Features for this product are very basic, minimal. There's no GPS use during your workouts, so you can't track where you have been and your pace. This product has a lot of potential if developed properly. Fitness enthusiasts may not like this product as much as Fitbit or Garmin."

Should you buy the Xiaomi Smart Band 9?

✅ Buy it if: You are a fitness beginner in search of an entry-level tracker, or a seasoned gym-goer on a tight budget. The Xiaomi Smart Band 9 offers an ultra-light and compact design, heaps of advanced health-tracking features and an impressively long battery life — all for less than $70.

❌ Don't buy it if: You want a fitness tracker that delivers precise heart rate measurements and GPS readings. Experienced exercisers and outdoor enthusiasts may be disappointed by the limited functionality of the Xiaomi Smart Band 9.

If Xiaomi Smart Band 9 is not for you

If you want good value for money, you can't go wrong with the Fitbit Inspire 3. For less than $100, this colorful fitness tracker offers excellent health tracking features, up to 10 days of battery life and a lightweight design. However, it does not feature GPS.

The Garmin Vivosmart 5 is another great alternative to the Xiaomi Smart Band 9. It is durable, jam-packed with tracking features and comfortable to wear. However, it costs nearly $150.

If you would rather invest in a smartwatch, check out the Amazfit Bip 3 Pro. This well-crafted fitness tracker allows you to control some of the features of your phone from your wrist, and comes with built-in Alexa voice control. At $69.99, it also price-matches the Xiaomi Smart Band 9.

Xiaomi Smart Band 9: How we tested

We spent over two months trying and testing the Xiaomi Smart Band 9, looking at its design, features, battery life, connectivity with third-party devices and ease of use. We wore it during the day, while sleeping and when doing a range of gym-based workouts, from high-intensity circuit classes to weightlifting. Finally, we assessed the accuracy of our Xiaomi Smart Band 9 by comparing its heart rate measurements with the data we obtained using a Polar H9 chest-strap heart rate monitor.

Following the inspection, the FDA sent Tom's of Maine a warning letter, which was posted publicly Tuesday (Nov. 19). The letter notes that inspectors observed "significant violations of Current Good Manufacturing Practice regulations" at the facility in Sanford, Maine.

One issue was that inspectors found a microbe called Pseudomonas aeruginosa in water samples used to rinse off equipment and to make toothpaste — specifically, Tom's Simply White Clean Mint Paste. The bacteria can cause a range of infections and is a particular problem in health care settings, in part because it can often be resistant to antibiotics.

Another microbe, called Ralstonia insidiosa, was also found in many water samples. This bacterial species can infect humans, but it does so infrequently.

Related: 39 sickened, 15 hospitalized in E. coli outbreak linked to organic carrots

In addition, Paracoccus yeei was found in a specific batch of Wicked Cool! Anticavity Toothpaste. This is another microbe that infects people "opportunistically." On the rare occasion it causes illness, it's most often seen in people with weakened immune systems.

In addition to these water-quality issues, an inspector found a black-mold-like substance in two damp areas in the facility. "The black substance was within one foot of stainless-steel pails and other product-contact equipment used for OTC [over-the-counter] drug production," the letter states.

In light of these and other findings, the FDA has requested an assessment of the company's manufacturing operations, along with a risk assessment of what could happen if any products were to be sold with "potentially objectionable contamination." The agency has requested that Tom's of Maine specify how the company will respond to that risk assessment and improve its water systems, facility management and cleaning procedures.

The FDA's inspection took place in May, and Tom's of Maine responded to its initial results in June. The FDA's latest letter declares that the company's June response was "inadequate," so the agency is calling for further action.

Tom's of Maine, which is owned by Colgate-Palmolive, has released the following statement to news outlets, including CNN:

"We're working with the FDA and are remedying the issues raised in their May inspection of the Tom's manufacturing plant in Sanford, Maine. We have always tested finished goods before they leave our control, and we remain fully confident in the safety and quality of the toothpaste we make."

"In addition," the statement continues, "we have engaged water specialists to evaluate our systems at Sanford, have implemented additional safeguards to ensure compliance with FDA standards, and our water testing shows no issues. We are also making capital investments as part of an ongoing, significant upgrade of the Sanford plant's water system. Tom's is committed to making safe and effective natural products for our consumers, and to maintaining the trust in our brand."

Ever wonder why some people build muscle more easily than others or why freckles come out in the sun? Send us your questions about how the human body works to community@livescience.com with the subject line "Health Desk Q," and you may see your question answered on the website!

Scientists with the Human Cell Atlas (HCA), an international research consortium, have profiled 100 million cells from more than 10,000 people around the world. Working in over 100 countries, the researchers aim to pinpoint similarities and differences in the cells of people from different demographics and genetic backgrounds.

By 2026, the team plans to unveil an atlas of the whole human body that details the location, identity and function of each cell at different stages of life. That atlas will just be a first draft; later iterations could include data from billions of human cells, the scientists project.

Now, HCA scientists have just dropped more than 40 papers that will aid in the construction of the groundbreaking first draft of their atlas. The research trove, published Wednesday (Nov. 20) in several Nature journals, charts cells in many organs and organ systems — including the lungs, brain and skin — and describes the advanced computational tools needed to crunch all those data.

Related: Most detailed human brain map ever contains 3,300 cell types

Aviv Regev, a founding co-chair of the HCA, compared the advance to leaps in traditional cartography. Imagine going from having only 15th-century maps of the world to having Google Maps, complete with detailed topographies, street views and dynamic traffic patterns.

"So that is the leap that we have done — moving from maps that look as crude as that to maps that are the resolution of the Google Map," Regev said at a news conference Tuesday (Nov. 19). "But we still have work to do."

The new research includes a detailed map of the digestive tract, running from the esophagus to the colon. The researchers mapped a healthy digestive tract based on 1.1 million cells sampled from nearly 190 people. They also compiled data from people with different gastrointestinal conditions, including ulcerative colitis and Crohn's disease. Through this work, they uncovered a type of cell that seems to contribute to the inflammation in these diseases, likely by summoning immune cells.

"Intestinal inflammation can cause cells to undergo metaplasia, a shift from one cell type to another," Itai Yanai, scientific director of the Applied Bioinformatics Laboratories at NYU Langone Health, wrote in a commentary. With data from both healthy and diseased guts, the researchers were able to pinpoint which stem cells gave rise to the "metaplastic" cells, Yanai said. After transforming, the metaplastic cells then spurred more inflammation, the research suggested.

In other papers, researchers opened a window into early human development, revealing how the placenta develops and the skeleton starts to form in the first trimester of pregnancy. The latter study revealed never-before-seen states that cells enter as they prepare to form the skull. The researchers also investigated genes that might be involved in craniosynostosis, a birth defect in which the soft spots of the skull fuse too soon.

Other papers focused on "organoids," miniature versions of human organs grown in the lab. One looked at brain organoids, which mimic developing brains. Different labs use various strategies to grow organoids, but that raises questions about which method produces the best model — which brain organoid best mimics an actual brain? The scientists compared maps of human brains to those of organoids, finding that, at least up to the second trimester, the organoids match fetal brains fairly closely. Open questions remain about the third trimester.

Related: Scientists launch amazing 'atlas' of embryos, showing how cells move and develop through time

Another lab ran a similar study looking at skin organoids, to see how closely they resembled real skin.

The atlas helps researchers come up with "better recipes" for organoids, Muzlifah Haniffa, a member of the HCA organizing committee, said at the news conference.

But "the information kind of flows both ways," Sarah Teichmann, an HCA co-chair, added, because the organoids also reveal subtle details of what's happening inside the body. Scientists can "poke the cells, perturb the cells" in ways that wouldn't be possible in human subjects, she said. Thus, making true-to-life organoids can help reveal how diseases arise and which drugs might effectively treat them.

Taken together, the more than three dozen HCA papers represent a major step forward. Meanwhile, data previously published by the consortium have already fueled new discoveries: Work published in 2020 helped reveal unexpected tissues that were vulnerable to COVID-19, and a map of the human lung revealed a new type of cell — the ionocyte — that may play a key role in cystic fibrosis.

"Collectively, the atlases have the potential to constitute a resource that others might be inspired to explore and compare with other biological contexts, such as different species and rare diseases," Yanai wrote. "Researchers might then discover aspects of the human body that cannot yet be imagined."

Ever wonder why some people build muscle more easily than others or why freckles come out in the sun? Send us your questions about how the human body works to community@livescience.com with the subject line "Health Desk Q," and you may see your question answered on the website!

The Irminger Sea off southeastern Greenland is where warm waters that transport heat northwards from the Southern Hemisphere sink and then return south along the bottom of the ocean. As such, this region plays a critical role in powering the ocean conveyor belt known as the Atlantic Meridional Overturning Circulation (AMOC).

"The key finding of this study is that the Irminger Basin (eastern Greenland) plays a crucial role in driving changes in the AMOC, a conclusion supported by recent observations," study lead author Qiyun Ma, a postdoctoral researcher at the Alfred Wegener Institute for Polar and Marine Research in Germany, told Live Science in an email. The work highlights the urgent need for better monitoring in this particular location, he said.

The AMOC, which includes the Gulf Stream, maintains a temperate climate in the Northern Hemisphere and regulates weather patterns across the globe. But due to climate change, the AMOC may not keep temperatures stable for much longer.

Research shows that Arctic meltwater gushing into the North Atlantic is reducing the density of surface waters and preventing them from sinking to form bottom currents, thus slowing the machine that powers the AMOC.

And it turns out the Irminger Sea is particularly important for keeping these bottom currents flowing.

Related: Earth is racing toward climate conditions that collapsed key Atlantic currents before the last ice age, study finds

"Freshwater release in this region not only directly inhibits deep-water formation — essential for maintaining the strength of the AMOC — but also alters atmospheric circulation patterns," Ma said. A reduction in the amount of water sinking in the Irminger Sea likely has greater impacts on the global climate than reductions of the same kind in other northern seas, Ma said.

The Irminger Sea has a disproportionate influence on the strength of the AMOC because it regulates the amount of water sinking to form deep currents in nearby seas through atmospheric processes, Ma said. Freshwater input into the Irminger Sea enhances freshwater flow into the Labrador Sea between southwestern Greenland and the coast of Canada, for example, so a reduction in deep-current formation in the Irminger Sea has knock-on effects for deep-current formation across the entire North Atlantic.

Ma and his colleagues examined the impact of meltwater on the AMOC using a climate model that simulated an increase in freshwater input in four regions — the Irminger Sea, the Labrador Sea, the Nordic Seas and the Northeast Atlantic. The researchers were able to tease out the sensitivity of the AMOC to meltwater in each region, then identified specific changes in the global climate linked to each scenario. The team published its findings Wednesday (Nov. 20) in the journal Science Advances.

The role of the Irminger Sea for the AMOC outweighed that of the three other regions in the model and triggered stronger climate responses. Reduced deep-water formation led to widespread cooling in the Northern Hemisphere, as well as Arctic sea ice expansion, because warm water wasn't being brought up from the south.

The simulation also showed slight warming in the Southern Hemisphere and bolstered previous findings that a weaker AMOC would throw tropical monsoon systems into chaos.

The model confirmed findings from previous research, but it also held surprises, Ma said. Hidden within hemisphere-scale climate shifts, the researchers discovered climate extremes at much more localized scales. These included seasonal extremes in precipitation across North America and the Amazon Basin that varied depending on which region of the North Atlantic meltwater was added into.

"While the general climate impacts … were broadly anticipated, the behavior of climate extremes was not," Ma said. Incorporating these extremes into climate models and recognizing that the location of meltwater input matters could help scientists better predict the impacts of a weakened AMOC, he said.

Forecasting AMOC behavior is becoming increasingly urgent as scientists warn we are nearing a tipping point. "These insights are critical for informing policy makers and climate experts in developing targeted strategies to mitigate and adapt to climate impacts," Ma said.

The moon is tidally locked with Earth, meaning the same side always faces our planet. The far side is less explored than the near side. Only two landers, both from China, have made it to the moon's far side.

In a study published Nov. 15 in the journal Science, researchers analyzed rock samples returned to Earth by the Chang'e 6 lander. The 2024 mission brought back a little over 4 pounds (1.9 kilograms) of rock from the South Pole-Aitken basin — the first samples ever brought to Earth from the moon's far side.

Zexian Cui of the Chinese Academy of Sciences' Guangzhou Institute of Geochemistry and colleagues analyzed the isotopes in these samples, as well as their chemical makeup, to find their age and source. Isotopes are atoms of an element that have the same number of protons in their nuclei but a different number of neutrons. The number of neutrons changes over time during radioactive decay, making the ratio of different isotopes in a sample a good way to measure how old that sample is.

Related: The oldest evidence of Earth's atmosphere may be hiding in rocks on the moon

The study found that the rocks — hardened lava called basalt — were 2.8 billion years old. Previous research had found volcanism on the near side of the moon until at least 2 billion years ago, and the new dates reveal that the far side of the moon was volcanically active as well. Another recent study of samples from the Chang'e 5 rover, which landed on the near side of the moon in 2020, even hints that volcanoes may have been erupting on the moon as recently as 120 million years ago.

The researchers also found that the lava that made the basalt came from a part of the moon's mantle that was low in potassium, rare Earth elements and phosphorus. These elements are widespread in the lava on the near side of the moon. The puzzling imbalance may be due to the impact crater that made the South Pole-Aitken basin, Cui and his colleagues wrote. The impact, which was large enough to reverberate all the way across the moon, may have redistributed rocks containing those elements, as well as melted the mantle directly below the impact site, depleting it of those elements.

The elemental imbalance may explain another odd difference between the two sides of the moon: Giant lava flows called mare basalts cover 30% of the near side but only 2% of the far side. Some of the missing elements on the far side, such as potassium and uranium, are radioactive and give off heat as they decay, the authors said. Their absence in the mantle under the moon's far side could explain the lack of these melty basalts.

From a distance, it might have looked like a small child was wending her way through the waving grass along a vast lake. But a closer look would have revealed a strange, in-between creature — a big-eyed imp with a small head and an apelike face who walked upright like a human.

She may have looked warily over her shoulder as she walked, on alert for saber-toothed cats or hyenas. She may have used her strong arms to climb the shrubby trees nearby, searching for fruit, eggs, or insects to eat. Or perhaps she simply rested on the shores of the croc-infested waters, gulping down water on a hot day.

She likely had no idea it was her last day on Earth.

Roughly 3.2 million years later, her skeleton was unearthed by paleoanthropologist Donald Johanson and his team on the International Afar Research Expedition.

The stunningly complete fossil was nicknamed "Lucy." And her remarkable species, Australopithecus afarensis, may have been our direct ancestor. Our discoveries about Lucy have transformed our understanding of humanity's tangled family tree.

Fifty years later, we know so much more about her species. In fact, anthropologists have learned so much about Lucy and her kind that we can now paint a picture of how she lived and died.

Her last day may have been filled with companionship, but it also entailed a relentless search for food. And it was likely dominated by the ever-present fear of predators.

"I suspect that the last day in her life was filled with danger," Johanson told Live Science.

Finding Lucy

The modern story of Lucy began on Nov. 24, 1974, in Hadar, Ethiopia. Johanson and then-graduate student Tom Gray stumbled upon a bone poking out of a gully. Following two weeks of careful excavation, their team recovered dozens of fossilized bones. Together, these bones made up 40% of the skeleton of a human ancestor, making it the most complete skeleton of an archaic human species that had ever been found.

Pamela Alderman, another member of the expedition, suggested the team nickname the skeleton Lucy, after the Beatles song "Lucy in the Sky with Diamonds."

"And it just became iconic," Johanson said, "a moniker that everybody knew."

Lucy’s discovery transformed the study of ancient human relatives.

"I was in high school when she was found," John Kappelman, a paleoanthropologist at the University of Texas at Austin, told Live Science. "It really did reset the way paleoanthropology worked."

Lucy's skeleton, along with subsequent discoveries of other fossils of her species, have given anthropologists a wealth of information about what is essentially the halfway point in human evolution. At 3.2 million years old, Lucy and her kind lived equidistant in time from our ape ancestors and contemporary humans.

"She's our touchstone," Jeremy DeSilva, a paleoanthropologist at Dartmouth College, told Live Science. "Everything sort of comes back to her as the reference point, and she deserves it."

"A lot like us"

One thing is fairly certain: Though there were some obvious differences, Lucy looked and acted a lot like us.

"If we saw her coming out of a grocery store today, we would recognize her as upright walking and some kind of human," Johanson said.

Although her strong arms and the shape of her finger bones suggest Lucy could climb trees, her pelvis and knees were clearly adapted to walking on two feet.

The size of Lucy's thigh bone also revealed that she was only about 42 inches (1.1 meters) tall and 60 to 65 pounds (27 to 30 kilograms) — about the size of a 6- or 7-year-old child today. And the eruption of her wisdom teeth showed that, although she was in her early teens when she died, she was a fully mature young adult.

"Australopithecus in general was maturing fast," DeSilva said, "and it makes sense if you're on a landscape full of predators." In species that are frequently prey, individuals that mature faster are more likely to pass on their genes. But australopithecines were unique—while their teeth and bodies matured quickly, their brains grew more slowly, telling us that they relied quite a bit on learning for survival, DeSilva said.

Her discovery also settled a debate that was raging in the early 1970s: Did our big brains evolve before we learned to walk upright? Lucy's head, which was not much bigger than a chimp's, showed the answer was no. Our ancestors became bipedal long before they evolved large brains.

Lucy's clan

Because her skeleton was found on its own, Lucy's "social life" is a little murkier than other parts of her daily life. But many researchers think she lived in a mixed-sex group of about 15 to 20 males and females, not unlike modern-day chimpanzees do.

And although there's no direct evidence, Lucy's skeletal maturity suggests she could have had a baby. Bringing that relatively large-headed newborn through her relatively narrow pelvis would have been challenging, which means she may have had the help of a primitive "midwife."

If Lucy had a baby, she also likely had a partner. Other A. afarensis fossils, such as those of Kadanuumuu, show male australopithecines were only slightly larger than females, which, in primates, usually corresponds to more monogamous pairings.

Lucy and her kind would have spent a significant amount of their time avoiding becoming another animals' lunch. "These small creatures would have been nice hors d'oeuvres for a sabertooth or a large cat or hyena," Johanson said.

Perhaps because of that omnipresent danger, the group likely relied on each other.

"I think they had each other's backs and helped each other out," DeSilva said, "especially when they were in dangerous situations."

A healed bone fracture seen in Kadanuumuu provides evidence that these primates cared for one another. Around 3.6 million years ago, this male australopithecine broke his lower leg. By the time he died, though, the break was fully healed.

"On that landscape with that many predators, no doctors, no hospitals, no casts, no crutches, how in the world do you survive if not for social assistance?" DeSilva said. "It's really strong evidence that they didn't leave each other for dead."

Lucy's last day

Lucy probably started her last day much like any other, waking up from the treetop nest made of branches and leaves where she slept, along with her group, before setting off to find food.

It's not clear whether she would have been alone or in a group when she left to forage; if she did have a baby, she may have carried it.

But there's no doubt that she would have spent a significant part of her day looking for food. She most likely ate a few staples, such as grasses, roots and insects, chemical elements in her tooth enamel showed. She may have happened upon the eggs of birds or turtles and promptly gobbled them up as tasty, protein-rich treats. And if she was lucky enough to come across a carcass of a large mammal, such as an antelope, that hadn't been picked clean, she and her troop mates may have pulled the flesh from the bone, using large rocks.

"They can't afford to be picky eaters as these slow bipeds in a dangerous environment," DeSilva said. "They're eating everything they can get their hands on."

However, there's no evidence that Lucy’s species used fire to cook any of their food.

Death at the water's edge

In the past 50 years, we've created a picture of Lucy's last moments. It's not clear exactly why she was by the lake; maybe she was thirsty, or perhaps it was a great spot to look for food.

But there are two main theories for how she died.

"Perhaps she was down there at the water and — bam! — a crocodile comes out," Johanson said. "Crocodiles are incredibly fast, and it's a dangerous place if you're a little creature" like Lucy.

Johanson found one carnivore tooth mark on Lucy's pelvis, and it had not healed, meaning it occurred around the time of her death. Although the animal that made the mark has not been conclusively identified, "we know that australopithecines were preyed upon because there are a number of examples," Johanson said.

In 2016, Kappelman and his colleagues put forward an alternate ending for Lucy: a catastrophic fall from a tree.

Based on high-resolution CT scans and 3D reconstructions of Lucy's skeleton, Kappelman identified fractures in her right shoulder, ribs and knees that were unlike the typical fracturing that occurs in fossils crushed under the weight of dirt and rocks for millions of years.

"Something traumatic happened here during life," Kappelman said.

The kinds of fractures Lucy suffered are consistent with a fall from a considerable height, perhaps from a tall tree in which she was foraging for food.

"She hit on her feet and then her hands, which meant she was conscious when she hit the ground," Kappelman said. "I don't think she survived very long."

It's not clear whether she was alone when she died. But even if she was with others of her kind, they likely wouldn't have done much with her body.

There's no evidence that A. afarensis "bodies were treated any differently than any other animal," DeSilva said. "Maybe there was some curiosity around it, and then they carried on."

Primate researchers have documented other species' curiosity about inanimate bodies. For example, chimpanzees often care for the body for a few hours or days after death, sometimes guarding the body.

Lucy's group may have done the same for her until her body was naturally buried, which would have happened quite rapidly, perhaps by a flood or mudslide.

In the end, though, "we know very little about how any of these creatures died," Johanson said.

Lucy lives on

Thanks to Johanson's 1974 discovery of Lucy — as well as other important findings, like the "First Family" and the footprints at Laetoli in Tanzania — we now know quite a lot about A. afarensis.

"It was a highly successful species that was comfortable in lots of different habitats," Johanson said; A. afarensis fossils have been found in Kenya in addition to Ethiopia and Tanzania. "From an evolutionary perspective, her species was highly adaptable," he said.

Lucy has had a broad impact on the field of anthropology.

"The discovery of Lucy really hit the start button for looking in older and older sediments in Africa," Kappelman said. As a result, we have found numerous ancient hominin species and now have 50 years' worth of fossil evidence that human evolution was messy and complex.

Lucy was the only human ancestor discovered at Hadar. But a couple dozen miles away at Woranso-Mille, a paleontological site in Ethiopia, Yohannes Haile-Selassie, director of the Institute of Human Origins at Arizona State University, and his colleagues have found evidence of a strange land inhabited by multiple humanlike species between 3.8 million and 3.3 million years ago. For instance, Lucy's kind coexisted alongside another ancient relative, A. anamensis.

Would they have been friends, enemies, competitors or something in between? Right now, anthropologists still have little idea what this landscape teeming with ancient hominins would have looked like.

But perhaps 50 years from now, we'll have a better picture of how Lucy's kind interacted with these other ancient hominins. Even then, Lucy will likely remain one of the most famous fossils of all time.

"I like to think all fossils are pretty special," DeSilva said, "but there's nothing like Lucy."

About 3.2 million years ago, our ancestor "Lucy" roamed what is now Ethiopia.

The discovery of her fossil skeleton 50 years ago transformed our understanding of human evolution. But it turns out her species, Australopithecus afarensis, wasn't alone.

In fact, as many as four other kinds of proto-humans roamed the continent during Lucy's time. But who were Lucy's neighbors, and did they ever interact with her kind?

For almost a million years, A. afarensis lived throughout East Africa, and paleoanthropologists have found numerous fossils of this species ranging from north central Ethiopia to northern Tanzania — a span of 1,460 miles (2,350 kilometers), or roughly the distance from Boston to Miami.

"It was a highly successful species that was comfortable in lots of different habitats," Donald Johanson, a paleoanthropologist at Arizona State University who, along with his graduate student Tom Gray, discovered Lucy's fossils in 1974, told Live Science.

For decades after Lucy's discovery, paleoanthropologists assumed A. afarensis was the only hominin that lived in this region during the middle Pliocene epoch (3 million to 4 million years ago). But the discovery of a fragmentary jawbone in the Bahr el Ghazal region of Chad in 1995 dramatically changed the picture of hominin diversity.

At 3.5 million years old, this fossil of a species that would be named Australopithecus bahrelghazali was the first indication that other hominins lived around Lucy's time, Yohannes Haile-Selassie, director of Arizona State University's Institute of Human Origins, and colleagues wrote in a study published in the journal PNAS in 2016.

Lucy's kind may not have interacted with these australopithecines, who were more than 1,500 miles (more than 2,400 km) away. But at the site of Woranso-Mille, just 30 miles (48 km) north of where Lucy was found at the site of Hadar in Ethiopia, Haile-Selassie and colleagues found A. afarensis fossils along with other, anatomically distinct fossils from the same time period.

These fossils belonged to a new australopithecine species: Australopithecus deyiremeda, which was dated to between 3.5 million and 3.3 million years ago. A. deyiremeda had markedly different teeth than Lucy's species, suggesting they had different diets, but paleoanthropologists do not currently agree on whether it is a different species from Lucy.

Woranso-Mille also yielded a partial foot dated to between 3.4 million and 3.3 million years ago, and its opposable big toe suggests this individual was better adapted for climbing than A. afarensis, a species that habitually walked on two legs. Although this individual was clearly not a member of A. afarensis, the "Burtele foot" has not yet been assigned to a species.

And at the Lomekwi site on the bank of Lake Turkana in Kenya, Meave Leakey, director of Plio-Pleistocene research at the Turkana Basin Institute in Kenya, and colleagues discovered another middle Pliocene hominin. The researchers named it Kenyanthropus platyops, Greek for "flat face". Dated to between 3.3 million and 3.2 million years ago, K. platyops overlapped in time with Lucy but lived over 620 miles (1,000 km) away.

K. platyops' brain was similar in size to that of A. afarensis, and the species lived in a grassy, lake-edge environment, much like Lucy did. While some researchers think K. platyops might be a Kenya-specific version of A. afarensis, others, including Haile-Selassie, think its upper teeth are different enough to call it a separate genus and species.

"A closer look at the currently available fossil evidence from Ethiopia, Kenya, and Chad indicates that Australopithecus afarensis was not the only hominin species during the middle Pliocene, and that there were other species clearly distinguishable from it by their locomotor adaptation and diet," Haile-Selassie and colleagues wrote.

This growing collection of fossils from different hominin species raises an important question that paleoanthropologists are trying to answer: Did these different species meet, or even mate with each other?

Almost all primates are social creatures, living in groups and cooperating to forage for food. And some nonhuman primates, such as tamarins, marmosets and howler monkeys, mate across species.

A. afarensis was as social as other primates, and Lucy may have lived in a group of 15 to 20 males and females. A preserved trail of footprints from three australopithecines walking together at the site of Laetoli in Tanzania is further evidence that Lucy and her kind were social creatures.

But there is currently little hard evidence that australopithecines mated across species, Rebecca Ackermann, a biological anthropologist at the University of Cape Town in South Africa, told Live Science in an email.

That said, "there is morphological evidence consistent with hybridisation in A. afarensis," particularly in the variation in their teeth," Ackermann noted. But these differences cannot be conclusively tied to interbreeding by current DNA techniques because australopithecine fossils are too old to harbor usable DNA.

Instead, we may be able to infer whether they ever interbred by looking at ancient proteins, which are coded for by DNA, she said. By looking at proteins in tooth enamel, Ackermann and colleagues clarified how individuals from the hominin species Paranthropus robustus, which lived in South Africa 2 million years ago, were related.

Despite the vast number of A. afarensis fossils discovered over the past half century, paleoanthropologists still have a lot of work ahead of them to fully understand the world Lucy inhabited.

"How these hominins were related to one another, how they interacted, how they filled niches on the landscape, and the degree of interbreeding that may have happened are open and important questions," Jeremy DeSilva, a biological anthropologist at Dartmouth College, told Live Science.

The near-complete skeleton, nicknamed "Vulcan," consists of exactly 300 bones, of which roughly 80% are authentic, and stretches to around 70 feet (21 meters) from end to end. It belonged to an Apatosaurus — a genus of plant-eating giants very similar to the iconic Brontosaurus — and roamed what is now North America in the late Jurassic period (201 million to 145 million years ago). Private collectors unearthed the fossils at an unnamed site in Wyoming between 2018 and 2021, according to French news agency AFP.

The stunning remains, which weigh more than 22 tons (20 metric tons), were put up for auction on Saturday (Nov. 16) at Dampierre-en-Yvelines — a chateau located around 30 miles (50 kilometers) southwest of Paris. The auction was won by an anonymous bidder who paid 6 million euros ($6.4 million) to land the skeleton.

Vulcan is now "the biggest dinosaur ever sold at auction worldwide," representatives from auction house Barbarossa, which co-ran the auction alongside Collin du Bocage, wrote online. It is unclear which fossil previously held this record.

The unnamed winner of the auction has promised that Vulcan will be put on public display "at an institution" and has agreed to give researchers access to study the bones, AFP reported.

Related: $25 million auction of T. rex skeleton called off at the last minute over replica bone controversy

Vulcan likely places 6th on the list of most expensive dinosaur fossils ever sold (although an exact list is hard to come by, especially when accounting for inflation). It is slightly less expensive than "Big John," the world's largest Triceratops, sold for $7.7 million in 2021, but slightly more pricey than an unnamed Gorgosaurus fossil and a Tyrannosaurus rex skull named Maximus, each sold for around $6.1 million.

The most expensive dinosaur fossil ever sold was "Apex," a near-complete Stegosaurus that was bought at auction for $44.6 million by billionaire Ken Griffin, according to Forbes — more than 11 times the original guide price.

Before then, the world's most expensive dinosaur was "Stan" — the 67-million-year-old T. rex that sold for $31.8 million in 2020. Stan became something of a celebrity after this sale when it disappeared for around two years before finally emerging in Abu Dhabi, despite rumors that it had been bought by actor Dwayne "The Rock" Johnson.

The current third-most-expensive dinosaur ever sold is "Hector" the Deinonychus — the species that inspired the appearance of the Velociraptors in the "Jurassic Park" movies — which was bought for $12.4 million in 2022.

Both sides of the bronze pendant feature inscriptions in ancient Greek. The text on the King Solomon side translates to "Our Lord defeated evil," while the other side names four angels: Azrael, Gabriel, Michael and Israfil.

"It is a symbol of religion and power," Ersin Çelikbaş, an archaeologist at Karabük University in Turkey who oversaw the excavation, told Live Science. The pendant was used as an amulet, a charm that was thought to protect against evil or danger, Çelikbaş added in a translated statement.

According to the Hebrew Bible, King Solomon was a ruler of ancient Israel during the 10th century B.C., but there is little archaeological evidence to confirm the biblical account.

Though Çelikbaş is certain that the artifact is a Christian pendant, "Solomon is an important figure in all three holy religions," he said in the statement. "While he is referred to as a ruler in the Torah and the Bible, he is also recognized as a prophet in Islam. The depiction of Solomon on this [pendant] surprised us and revealed the importance of the artifact for Anatolian archaeology."

Related: Rare gladiator-shaped knife handle discovered by Hadrian's Wall

Archaeologists uncovered the pendant during excavations at Hadrianopolis. This ancient settlement in Paphlagonia, a region in north-central Turkey on the coast of the Black Sea, became a city under the Romans. It was called Hadrianopolis for the Roman emperor Hadrian, who ruled from A.D. 117 to 138, and was rebuilt in the Early Byzantine period. Today it is located in the vicinity of the city Karabük. 

The site of the ancient city is famous for its animal mosaics, and excavations have revealed baths, churches, fortifications, burials, a theater, villas and other structures, the statement said. The pendant was discovered in a building that might be related to military activity, although its function is still unknown, Çelikbaş told Live Science.

"In our previous excavations, we had determined the existence of a cavalry unit here," he said in the statement. "Prophet Solomon is also known as the commander of armies. We understand that he was also considered as a protective figure for the Roman and Byzantine cavalry in Hadrianopolis." In fact, Çelikbaş hypothesized that the pendant belonged to a cavalry soldier.

Based on the archaeological layer where they found the pendant, the archaeologists dated the artifact to the fifth century, when Hadrianopolis was part of the Byzantine Empire, he added. Emperor Constantine, who ruled a few centuries after Hadrian, later split the Roman Empire in two, leading to the creation of the Byzantine Empire in A.D. 330.

Although the pendant is the first of its kind discovered in Anatolia, Çelikbaş is aware of one previously found in Jerusalem. "The presence of similar artifacts in these two distant geographies indicates that Hadrianopolis was an important religious center in ancient times," he said in the statement.

The pendant is now in his lab, and he will eventually hand it over to a museum to exhibit it.

Editor's note: This article was updated at 1:15 p.m. EST to note that the amulet was found in Hadrianopolis in Paphlagonia, an ancient region of what is now Turkey, not in another Hadrianopolis that was formerly called Uskudama.

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