Many chickens meet their end with a swift blow to the neck. But there's lore that chickens can run around headless, and there were even news reports of a chicken nicknamed Miracle Mike who reportedly lived 18 months after a farmer tried ‪—‬ and failed ‪—‬ to kill it by cutting off its head.

So can chickens really survive without their heads?

The reality is that they can't live long that way ‪—‬ less than a minute, experts told Live Science.

After decapitation, chickens commonly flap their wings and move their legs, said Dr. Marcie Logsdon, a veterinarian in the Exotics and Wildlife Department at Washington State University's Veterinary Teaching Hospital in Pullman, Washington. However, "I think the actual running around is fairly uncommon," Logsdon said. "It's usually just going to be strong muscle contractions of both the wings and the legs, and that's a very common thing," she said. Those movements typically last a minute or less, she added.

However, the answer to whether a chicken is alive or dead in the seconds following decapitation depends on how death is defined. In the case of a decapitated chicken, brain death occurs first, while cardiac death happens a few seconds later. So, in those moments after brain death and before cardiac death, one could view the chicken as either alive or dead, depending on the definition of death used.

Brain death is a state of unconsciousness in which the entire brain is permanently damaged and an individual cannot breathe on their own. Brain electrical activity in chickens stops within 30 seconds after cervical dislocation (breaking the neck), according to a 2019 study published in the journal Animals. Decapitation includes breaking the neck, so according to the framework of brain death or loss of brain activity, chickens survive a few seconds after decapitation.

"That is not to say that the animals are consciously aware of anything happening for those seconds, but there is residual electrical activity occurring," Andrew Iwaniuk, a comparative neuroscientist at the University of Lethbridge in Alberta, Canada, who specializes in bird brains, told Live Science.

Cardiac death, which happens when the heart permanently stops beating, tends to occur a few seconds after brain death, Iwaniuk said. "The time difference would be in the order of less than 10 seconds," he said.

As a result of these different definitions of death, Logsdon considers a chicken's post-decapitation movements "post-mortem reflexes," whereas Iwaniuk views the chicken as alive during those last stirrings.

Chickens move after decapitation because "there'll be some residual neural activity in the spinal cord," Iwaniuk said. Continued breathing is also due to residual neural activity, he said. The heart muscles, on the other hand, can continue to contract and release without neural input — until they run out of energy and oxygen, he said.

Further, the brain normally sends signals telling the muscles to relax when they aren't needed, Logsdon said. Decapitating a chicken stops those signals, and when that happens, "we sometimes get some jerking," Logsdon said. "That does seem to be very exaggerated in chickens."

Miracle Mike

Something very different happened in the case of Miracle Mike. In September 1945, the BBC reported in 2015, Wisconsin farmer Lloyd Olsen decapitated a group of chickens to take to market, but one of them didn't die. For 18 months, the rooster, who came to be known as Miracle Mike, toured the U.S. in sideshows. Olsen and his wife fed the rooster through its esophagus and cleared its airway to try to keep it from choking, but it did eventually choke to death in 1947, after the Olsens misplaced the throat-clearing syringe, the BBC reported.

This story may seem to illustrate that a chicken can live without its head. But the reality is that there's only one widely known case of a chicken living without some of its head. Instead of beheading Mike by cutting straight across the neck, Logsdon explained, the farmer "cut off a chunk of the brain and essentially most of the face."

Mike's decapitation left him with the back of his brain as well as one ear, the BBC noted. He likely retained the brainstem, located at the back of the brain, which controls basic physiological functions like breathing and heart-rate regulation, Iwaniuk said. Mike probably also had his cerebellum, which helps coordinate movements, Logsdon said.

"It's probably why he was able to actually stand up and walk, as opposed to just running around and flailing," Logsdon said.

How much do you know about our feathered friends? Test your knowledge with our bird quiz!

After death, a series of natural processes begin within the human body. The corpse cools, pales and stiffens before it begins to decompose. The stiffening of the corpse is called rigor mortis. It's viewed as macabre, creepy and unsettling, and it's been used as a plot device in crime shows, a jump scare in horror films, and a clue in movie mysteries.

But what, exactly, is this process, and why does it happen to nearly all bodies?

Rigor mortis is a natural process that occurs at a cellular level. It begins immediately after death as the body runs out of adenosine triphosphate, the energy molecule commonly known as ATP. "You can essentially think of [ATP] as your fundamental source of energy for muscle contraction," said Dr. Michelle Jorden, chief medical examiner of Santa Clara County and president of the National Association of Medical Examiners. "The ATP molecule is what's needed for us to move."

After death, the body stops producing ATP, and its supply of the energy molecule is depleted within a couple of hours, on average, Jorden said.

The body needs ATP not only to move but also to relax. As the body's supply of ATP runs out, the muscle filaments — proteins bound together within muscle cells — begin to stick together.

One misconception is that the body snaps into rigor instantly. While rigor mortis starts immediately in all muscles following death, in most cases it can take several hours before it becomes visible to the naked eye as filaments stick together.

Between two and six hours after death, stiffness first appears in the body's smallest muscles in the face. After six to 12 hours, it progresses through larger muscles in the hands, arms and neck and chest. Finally, the body's largest muscles in the lower body stiffen — full-body rigor mortis happens between 12 and 24 hours after death, completing this sequence known as the "march of rigor."

Another misconception about rigor mortis is that it's permanent — that, once stiffened, the body will stay that way forever. "It's a transitional phase, not a permanent state," said Shawn'te Harvell, a licensed funeral director in New York and New Jersey and president of the National Funeral Directors & Morticians Association.

Rigor mortis lasts around 24 to 48 hours and then disappears once decomposition begins, when "muscles become flaccid again as the decomposition breaks down protein structures," he said. The body becomes flaccid in the same order it stiffened — starting with the face and hands, down the neck and torso, and then the legs.

This timeline is a guideline, Harvell said, and the process is unique for each body. Factors such as temperature, age and activity level at the time of death; overall health and body composition; and medications taken during life affect how quickly or slowly the body goes through rigor mortis before decomposition sets in. "No two cases follow exactly the same timeline or intense pattern," he said.

Jorden, a practicing forensic pathologist and neuropathologist, said that determining the timing of rigor mortis can be "a very valuable tool" for assessing the scene of a death.

"[It] can actually provide clues if the body has been manipulated or moved," she said. What's more, if the timing of rigor mortis doesn't quite line up with what they believe the circumstances of death were, it may be a clue that "causes us to pause and ask more questions."

When Roro (not her real name) lost her mother to cancer, the grief felt bottomless. In her mid-20s and working as a content creator in China, she was haunted by the unfinished nature of their relationship. Their bond had always been complicated — shaped by unspoken resentments and a childhood in which care was often followed closely by criticism.

After her mother's death, Roro found herself unable to reconcile the messiness of their past with the silence that followed. She shared her struggles with her followers on the Chinese social media platform Xiaohongshu (meaning "Little Red Book"), hoping to help them with their own journeys of healing.

Her writing caught the attention of the operators of AI character generator Xingye, who invited her to create an AI version of her mother as a public chatbot.

"I wrote about my mother, documenting all the important events in her life and then creating a story where she was resurrected in an AI world," Roro told me through a translator. "You write out the major life events that shape the protagonist's personality, and you define their behavioral patterns. Once you've done that, the AI can generate responses on its own. After it generates outputs, you can continue adjusting it based on what you want it to be."

During the training process, Roro began to reinterpret her past with her mother, altering elements of their story to create a more idealized figure — a gentler and more attentive version of her. This helped her to process the loss, resulting in the creation of Xia (霞), a public chatbot with which her followers could also interact.

After its release, Roro received a message from a friend saying her mum would be so proud of her. "I broke down in tears," Roro said. "It was incredibly healing. That's why I wanted to create something like this – not just to heal myself, but also to provide others with something that might say the words they needed to hear."

Grief in the age of deathbots

As I recount in my new book Love Machines, Roro's story reflects the new possibilities technology has opened for people to cope with grief through conversational AI. Large language models can be trained using personal material including emails, texts, voice notes and social media posts to mimic the conversational style of a deceased loved one.

These "deathbots" or "griefbots" are one of the more controversial use cases of AI chatbots. Some are text-based, while others also depict the person through a video avatar. US "grieftech" company You, Only Virtual, for example, creates a chatbot from conversations (both spoken and written) between the deceased and one of their living friends or relatives, producing a version of how they appeared to that particular person.

While some deathbots remain static representations of a person at the time of their death, others are given access to the internet and can "evolve" through conversations. You, Only Virtual's CEO, Justin Harrison, argues it would not be an authentic version of a deceased person if their AI could not keep up with the times and respond to new information.

But this raises a host of difficult questions about whether estimating the development of a human personality is even possible with current technology, and what effect interacting with such an entity could have on a deceased person's loved ones.

Xingye, the platform on which Roro created her late mother's chatbot, is one of the key prompts for proposed new regulations from China's Cyberspace Administration, the national internet content regulator and censor, which seek to reduce the potential emotional harm of "human-like interactive AI services".

What does digital resurrection do to grief?

Deathbots fundamentally change the process of mourning because, unlike seeing old letters or photos of the deceased, interacting with generative AI can introduce new and unexpected elements into the grieving process. For Roro, creating and interacting with an AI version of her mother felt surprisingly therapeutic, allowing her to articulate feelings she never voiced and achieve a sense of closure.

But not everyone shares this experience, including London-based journalist Lottie Hayton, who lost both her parents suddenly in 2022 and wrote about her experiences recreating them with AI. She said she found the simulations uncanny and distressing: the technology wasn't quite there, and the clumsy imitations felt as if they cheapened her real memories rather than honored them.

There are also important ethical questions about whose consent is required for the creation of a deathbot, where they would be allowed to be displayed and what impact they could have on other family members and friends.

Does one relative's desire to create a symbolic companion who helps them make sense of their loss give them the right to display a deathbot publicly on their social media account, where others will see it – potentially exacerbating their grief? What happens when different relatives disagree about whether a parent or partner would have wanted to be digitally resurrected at all?

The companies creating these deathbots are not neutral grief counsellors; they are commercial platforms driven by familiar incentives around growth, engagement and data harvesting. This creates a tension between what is emotionally healthy for users and what is profitable for firms. A deathbot that people visit compulsively, or struggle to stop talking to, may be a business success but a psychological trap.

These risks don't mean we should ban all experiments with AI-mediated grief or dismiss the genuine comfort some people, like Roro, find in them. But they do mean that decisions about "resurrecting" the dead can't be left solely to start-ups and venture capital.

The industry needs clear rules about consent, limits on how posthumous data can be used, and design standards that prioritize psychological wellbeing over endless engagement. Ultimately, the question is not just whether AI should be allowed to resurrect the dead, but who gets to do so, on what terms, and at what cost.

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This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

In late December 1985, a worker opened the door to a remote cabin in the Virunga Mountains of Rwanda and encountered a horrific scene: Gorilla researcher Dian Fossey, whose aggressive approach to conservation had pitted her against the local community, had been hacked to death with a machete, and her cabin had been ransacked.

Fossey had been working with an endangered gorilla population in Rwanda's Volcanoes National Park since the late 1960s. Along with Jane Goodall and Biruté Galdikas, she was one of the three "trimates" chosen by Louis Leakey to study primates in their natural habitat.

Fossey had no formal training in ethology, the science of animal behavior, when she set out for Africa. She began her field work in Kabara, Congo, living in a tiny tent and venturing out to study mountain gorillas (Gorilla beringei beringei) there. After civil war broke out in 1967, she escaped to the Rwandan portion of the mountains and set up a new research project near Mount Karisimbi in Rwanda.

Fossey was inspired by the work of George Schaller, a biologist who, in 1959, had also studied the gorillas of the Virunga Mountains.

"I knew that animals try to stay out of your way. If you go quietly near them, they come to accept your presence. That's what I did with gorillas. I just went near them day after day, which was fairly easy because they form cohesive social groups. Soon, I knew them as individuals, both their faces and their behavior, and I just sat and watched them," Schaller said in a 2006 interview.

Fossey operated on this same principle of patient, unobtrusive observation. Still, the gorillas initially fled from her, and she spent hours tracking and trailing them across the misty forest.

After a year, they stopped fleeing at her presence and started beating their chests and vocalizing. It was a bluff meant to scare her off, but it was still far from their ordinary, natural behavior, she said in a 1973 lecture. After two years, she received two young gorillas, Coco and Pucker; rehabilitated them; and learned about gorilla young by observing them.

"I came to know the gorillas' need for love and affection, and the young gorillas' need for constant play," she said.

It would take three years before the gorillas came to accept her presence and reveal more naturalistic behavior, she said in the lecture.

During her decades in Virunga, Fossey described and learned to mimic the vocalizations of gorillas, including the "belch vocalization" that signifies contentment. She also elucidated their tight-knit family structures, courtship and mating rituals, as well as documented the occasional murder of infant gorillas by rival males.

Although she would eventually earn her doctorate in zoology from the University of Cambridge, Fossey spent her first years studying the gorillas with no formal training. Perhaps because of her initial lack of training, she formed close bonds with individual animals and tended to ascribe more humanlike motivations and descriptions to their actions than is typically accepted in formal zoology. She often described gorillas as more altruistic than humans.

"You take these fine, regal animals,'' she told an interviewer, as reported by The New York Times. ''How many fathers have the same sense of paternity? How many human mothers are more caring? The family structure is unbelievably strong.''

She formed a particularly close bond with a gorilla she nicknamed Digit — so named for his damaged finger — who did not have playmates his age. Digit was killed by poachers in 1977.

The last years of Fossey's life were increasingly focused on conserving the gorillas' dwindling habitat and combating poachers. She used confrontational methods, such as burning snares, wearing masks to scare poachers, and spray-painting cattle to prevent herders from bringing them into the national park, according to the Dian Fossey Gorilla Fund.

She also shot over the heads of tourists to scare them away and told her graduate students to carry guns, according to The Washington Post.

Given that many of the people living on the fringes of the park lived in poverty and resorted to expansion and herding to survive, this did not earn her good will with many of the locals.

Fossey's murder was never solved. Many think poachers were responsible for the killing, but other theories have been floated as well.

Most of the time, death is permanent — when someone's heart stops beating, it rarely starts again. But sometimes, first responders can help bring a person back from the dead even after their heart stops.

So what's the longest time that someone has been clinically dead and come back to life?

Generally, spending more than 30 minutes "dead" and coming back without major brain damage is rare. But in some specific circumstances, people have been resuscitated after many hours and made a full recovery.

To understand how this happens, it's first important to define exactly what death is.

"Most of the time when [doctors] say 'clinically dead,' we're talking about cardiac death, and that means your heart is no longer beating," Dr. Daniel Mark Rolston, an emergency medicine physician at Northwell Health in New York, told Live Science.

When someone's heart stops beating, all of the cells in their body — and, most importantly, their brain — no longer receive fresh, oxygenated blood. After about five minutes without oxygen, those cells start to die, a process that can't be reversed.

The other type of clinical death is brain death, which occurs when the brain is so damaged that it can no longer control basic life functions, such as breathing and heartbeat.

How resuscitation works

Cardiopulmonary resuscitation (CPR) is designed to keep fresh blood flowing throughout the body and keep brain cells alive after cardiac death. By manually compressing the chest and giving rescue breaths, first responders can help keep cells oxygenated for a short period of time even when the heart isn't beating on its own. Most of the time, CPR can't restart the heart itself, but it can buy time for other techniques that can.

To get the heart to beat on its own again, first responders use a technique called defibrillation. This applies an external electrical current to the heart, mimicking the natural electrical signals that the heart muscles use to contract. In some cases, these electrical signals can reset the heart and help it beat again.

Under ideal conditions, these life support techniques can be relatively successful. According to the American Red Cross, survival rates following CPR in a hospital are about 20%. Those rates drop when people undergo cardiac arrest outside the hospital, falling to about 10%. That's because outside of healthcare settings, fewer people are trained in CPR and response times are generally slower.

"The earlier you get it, the better the outcomes," Rolston explained.

But even in the best-case scenarios, successful resuscitation after more than half an hour is rare, even if CPR is administered continuously.

"For the vast majority of people with very prolonged cardiac arrest periods, the survival is pretty poor," Rolston said. "If you don't get someone back at 30 minutes, their likelihood of survival is pretty low at that point."

Buying time with hypothermia

There is one notable exception to this rule, though: cases where cardiac arrest is combined with hypothermia. Hypothermia occurs when the core body temperature drops below 95 degrees Fahrenheit (35 degrees Celsius), and on its own, it can be very dangerous, causing the heart and lungs to fail, eventually leading to death.

But if the heart has already stopped on its own, hypothermia can actually have some upsides. Cold temperatures slow down the body's metabolism, protecting the delicate cells in the brain from dying after using up all of their oxygen.

"If you get cold fast enough, it can protect you for a long time," explained Dr. Samuel Tisherman, a professor of surgery at the University of Maryland School of Medicine who studies how hypothermia could be used as a therapeutic measure in cases of cardiac arrest due to trauma. "There are numerous reports of people drowning in very cold water and being underwater for upwards of an hour and surviving."

The longest-known reported case of successful resuscitation after cardiac arrest and accidental hypothermia is of a 31-year-old man who was revived after eight hours and 42 minutes. The man, whose body temperature was already about 79 F (26 C) due to a summer thunderstorm, experienced a cardiac arrest, and people nearby immediately began administering CPR, which was maintained for over three and half hours. Once the man was at a hospital, he was placed on a life support system that maintained fresh blood flow for five hours, and he was eventually warmed and successfully resuscitated. After three months, doctors reported that the man had completely recovered, with no sustained neurological damage.

What about coming back to life from brain death?

While cardiac death has possible roads to recovery, brain death is another story. When a patient is declared brain dead, it means their brain can no longer send signals to the body that control essential functions.

To be declared brain dead, doctors need to identify what medical issue is causing the brain damage and rule out any conditions that could cause symptoms that resemble brain death. This process can involve imaging the brain using MRI, testing basic neurological functions such as pupil dilation reflexes, and checking whether the patient can breathe on their own.

Every now and then, a news story pops up about a patient who was declared brain dead and taken off life support, only for them to "come back to life." So are these patients really rising from the dead?

In all likelihood, probably not. The definition of brain death is that the basic life-supporting regions of the brain are so damaged they won't be able to recover, so brain death isn't a condition that can be reversed. What's most likely happening in cases when someone supposedly recovers is that the original diagnosis of brain death was wrong.

"Errors have been made where people declared brain dead were later found to have spontaneous movement that should not have been possible," Dr. Robert M. Sade, a professor of surgery at the Medical University of South Carolina, told Medscape in 2018. "In virtually all those cases, brain-death determination was not done correctly."

If you want to know your chronological age, simply count the candles on your next birthday cake. Calculating your biological age, though, is a little more complicated.

Chronological age is the number of years between your birth and now; it's purely time-based. Biological age, on the other hand, describes the progressive breakdown of an individual's physiological and molecular systems over time; it's a measure of how "aged" the body is. The calculation aims to answer the question of how well your systems, organs and cells are working compared to an average, healthy baseline.

"Biological age is notoriously hard to define because it's very much a conceptual notion," said Eric Sun, an assistant professor of biomedical engineering at MIT, where he will launch a new lab starting in 2026. The concept requires you to think less about pure chronology and more about how your body is performing over time, and what your risks and vulnerabilities for various diseases might be in the future, he said.

Scientists have devised a number of "clocks" aimed at determining people's biological ages. Here's how they work and why they might be useful.

Neither Henderson nor Sun thinks modern aging clocks are ready for clinical use. There's still too much noise in the data, too much potential for drawing faulty conclusions about what drives aging and what's just associated with it, Henderson told Live Science. If aging clocks were used to help doctors determine what treatment course a patient needs, false positives could lead to unnecessary medical intervention.

Sun told Live Science he believes future clocks that get adapted for patients will bear similarities to the fourth-generation causal clocks that already exist.

"It won't just be biomarkers for how your entire body or even individual systems are aging," he said, "but multiple biomarkers for different functions within an organ."

This article is for informational purposes only and is not meant to offer medical advice.

NASA astronaut Jim Lovell, who helped turn the near-disastrous Apollo 13 moon mission into an inspiring tale of ingenuity and survival, has died at the age of 97.

Jim Lovell passed away on Thursday (Aug. 7) in Lake Forest, Illinois, according to NASA officials. But the astronaut, a veteran of four pioneering spaceflights, left a mark on the agency and the nation that will last far into the future.

"Jim's character and steadfast courage helped our nation reach the moon and turned a potential tragedy into a success from which we learned an enormous amount," acting NASA Administrator Sean Duffy said in a statement on Friday (Aug. 8). "We mourn his passing even as we celebrate his achievements."

Lovell joined NASA in September 1962, as part of the agency's second-ever astronaut class. Among his eight colleagues in that group were Apollo 11 moonwalker Neil Armstrong and Ed White, the first American to walk in space.

Lovell first flew to space in December 1965 on Gemini 7, a two-person, two-week-long mission that featured the first-ever rendezvous of two maneuverable crewed spacecraft in Earth orbit. The two-astronaut Gemini 6A capsule came within a mere foot or so of Gemini 7 (carrying Lovell and Frank Borman) high above our planet on Dec. 15 of that year.

On Nov. 11, 1966, Lovell and Buzz Aldrin launched on Gemini 12, which circled Earth for four days. It was the final mission of the Gemini program, which was designed primarily to help pave the way for the Apollo moon push.

Related: Scientists scan famous 'Earthrise' crater on mission to find alien life in our solar system

Lovell's third spaceflight was Apollo 8, the first crewed mission ever to go beyond Earth orbit. He served as command module pilot and navigator on the six-day flight in December 1968, which successfully went to lunar orbit and back. His crewmates were Borman and William Anders, who snapped the famous "Earthrise" photo on Christmas Eve of that year.

Then came Apollo 13 in April 1970, during which Lovell became the first person ever to reach space four times. He commanded the mission, which also included lunar module pilot Fred Haise and command module pilot Jack Swigert.

Lovell and Haise were supposed to become the fifth and sixth people ever to walk on the moon, but things didn't go according to plan. An oxygen tank in the mission's command and service module exploded, damaging the spacecraft and forcing the three astronauts into survival mode.

They abandoned their moon-landing plans and, working in concert with Mission Control in Houston, "converted their lunar module 'Aquarius' into an effective lifeboat," NASA officials wrote in Lovell's official biography.

"Their emergency activation and operation of lunar module systems conserved both electrical power and water in sufficient supply to assure their safety and survival while in space and for the return to Earth," the officials added.

Lovell wrote about this experience in "Lost Moon: The Perilous Voyage of Apollo 13" (Houghton Mifflin, 1994). The book, which he co-authored with science journalist Jeffrey Kluger, became the basis for the 1995 movie "Apollo 13," starring Tom Hanks as Lovell.

That movie, incidentally, popularized the phrase "Houston, we have a problem." But it's not entirely accurate; the actual quote — uttered by both Lovell and Swigert — is "Houston, we've had a problem."

James A. Lovell was born in Cleveland, Ohio, on March 25, 1928. He graduated from the U.S. Naval Academy in 1952 with a bachelor of science degree. That same year, he married Marilyn Gerlach; they would have four children together. (Marilyn passed away in September 2023.)

From 1958 to 1962, Lovell served as a test pilot at the Naval Air Test Center in Patuxent River, Maryland. For part of that time, he was manager for the Navy's F4H "Phantom" Fighter program, which put into service supersonic jets built by McDonnell Douglas.

Overall, Lovell logged more than 7,000 hours of flying time, more than half of which came in jet aircraft, according to his NASA biography.

Lovell retired from the Navy and from NASA in March 1973, two years after completing the Advanced Management Program at Harvard Business School. He then held several high-level jobs, including executive vice president of the Chicago-based telecom company Centel Corp., a post from which he retired on Jan. 1, 1991.

Lovell had been the oldest surviving Apollo astronaut. That distinction now goes to Aldrin, who is 95. Only five of the 24 astronauts who flew to the moon during the Apollo era are still alive: Aldrin, Charles Duke, Harrison Schmitt, David Scott and Lovell's Apollo 13 crewmate Fred Haise.

This article was originally published on Space

The deceased: A 39-year-old woman in Belgrade, Serbia

The discovery: The woman's ex-husband found the woman's body in her apartment and notified the police. She was lying on her left side on the living room couch, and her body was covered by a blanket.

What happened next: Police removed the blanket to examine the body; the woman was naked from the waist down. There were no visible signs of violence or injury. The police then discovered an object protruding from the woman's bottom: a spring twirl whisk.

Its wooden handle had been inserted into her anus to a depth of about 4 inches (10 centimeters), penetrating her anus and rectum as "a dildo-like object," doctors wrote in a report of the case. According to the ex-husband, the woman had high blood pressure, also known as arterial hypertension, for which she was taking medication.

The autopsy findings: An examination of the woman's cranium revealed a subarachnoid hemorrhage — bleeding in the space between the brain and a layer of tissue surrounding it. Blood had pooled to a depth of up to 0.2 inches (6 millimeters) around the base of the brain and the brainstem.

When medical examiners cleared out the blood clots, they discovered a ruptured saccular aneurysm, a blood-filled sphere that ballooned from a blood vessel in the brain. This is also known as a "berry aneurysm" for its resemblance to a round berry dangling from a stem, and it is the most common type of aneurysm.

The aneurysm measured 0.4 inches (11 millimeters) in diameter and had popped at the top of its dome. When aneurysms rupture, they release blood that can kill nearby brain cells and increase pressure inside the skull. As pressure builds, the flow of oxygen and blood to the brain may be disrupted, which can lead to unconsciousness and death. Aneurysms are more common in women than in men, especially in women with low estrogen levels, such as postmenopausal women. People with hypertension are also more likely to develop aneurysms that rupture and cause bleeding in the brain.

Physical exertion raises blood pressure, and orgasms elevate it even more. In the woman's case, her partial nudity, body posture and the presence of the whisk suggested that she was using the kitchen tool for anal self-stimulation, the report's authors wrote. Her sexual excitement and subsequent orgasm could have temporarily caused her blood pressure to spike enough to rupture the aneurysm, causing a fatal hemorrhage.

What makes the case unique: Sexual activity is not a common cause of sudden death. In prior studies that evaluated a total of nearly 130,000 forensic autopsies, 195 of the deaths (0.15%) were linked to sex, and only a fraction of the deceased were women. When someone dies during or shortly after intercourse, it is usually an older male with a much younger female partner, and the cause of death is typically abrupt cardiac failure, according to the report.

For women, sudden death during sex is often caused by a subarachnoid hemorrhage from a burst saccular aneurysm. However, this is the first case to present such a scenario for a woman's death during anal self-stimulation, the authors wrote.

This article is for informational purposes only and is not meant to offer medical advice.

This amulet, shaped like a scarab beetle, was discovered in the tomb of an ancient Egyptian noblewoman named Hatnefer. But the charm, which was intended to assist her journey to the afterlife, was not originally made for her.

The scarab was carved from serpentinite, a greenish-gray metamorphic rock, and measures roughly 2.6 inches (6.6 centimeters) long. It was set in gold and suspended on a 30.5-inch-long (77.5 cm) plaited gold chain. This exquisite necklace was excavated in the 1930s from the tomb of Hatnefer and her husband Ramose and is on display at The Metropolitan Museum of Art in New York City.

Hatnefer's mummy and tomb contents suggest she was powerful in her own domain. She was about 60 years old when she died, and she was buried with bronze and silver mirrors, cosmetics and wood chests full of high-quality linen.

According to The Met, Hatnefer's scarab includes a version of the Book of the Dead chapter on heart weighing, and her name has been inserted over text that was previously erased, suggesting that the amulet was not originally intended for her.

Related: Hårby Valkyrie: A 1,200-year-old gold Viking Age woman sporting a sword, shield and ponytail

The Book of the Dead passage engraved on the bottom of the scarab discusses the weighing of the heart. In ancient Egypt, the heart was considered the most important organ, as it was thought to be the location of a person's intelligence and memory. After a person died, their heart was weighed by Ma'at, the goddess of truth and justice, to determine if the person led a life worthy of entering the Duat, or the underworld. The "heart scarab" was meant to silence the heart of the deceased so that it could not lie about or misrepresent its owner. Peter Dornan, former curator of Egyptian art at The Met, translated the cuneiform script on Hatnefer's heart scarab as follows:

The Mistress of the House, Hatnefer, says: "Heart of my mother, heart of my mother, heart of my (actual) being, do not rise up against me as a witness; do not contend against me in the court of judgment; do not make opposition against me in the presence of the keeper of the balance. You are my bodily ka, a Khnum who has invigorated my limbs. When you ascend to the perfection from which we have come, do not cause our names to stink to the entourage who create mankind in their proper stations, but rather may it go well with us and with the listener, so that the judge may rejoice. Do not devise lies against me in the presence of the god, for your reckoning is at hand."

According to legend, when an elephant knows it's nearing the end of its days, it will return to a specific place to die among the remains of its kin, and over time, these remains will form "elephant graveyards" that tower with tusks and skulls.

The idea is so powerful that it has made its way into popular culture, such as in Disney's "The Lion King," where haunting images of an elephant cemetery seared themselves onto the minds of a generation of children. Such graveyards hint at the tantalizing prospect that elephants might understand and anticipate their own mortality. But do these places really exist, and do elephants know when they are about to die?

In Africa and elsewhere, there are rare instances when a large number of elephant carcasses are found in a relatively confined area, said Leanne Proops, an associate professor of animal behavior and welfare at the University of Portsmouth whose research looks at death-related behaviors in animals. But in these occasional cases, the pile of carcasses has been linked to drought, large-scale poaching, geological forces or toxic algal blooms in water holes, which have been found to poison hundreds of elephants in one go.

What researchers have been unable to show is that these graveyards form because elephants intentionally traveled there to die, Proops told Live Science. "I can see where that myth or idea could have come into popular culture," she said, but that's exactly what it is: a myth, she said.

Akashdeep Roy, a researcher at the Indian Institute of Science Education and Research, agreed. "I'd be very cautious about using the term 'graveyard,'" he said. "The idea of a graveyard that persists is largely a myth fueled by locals and hunters."

Related: Do elephants really 'never forget'?

Do elephants bury their dead?

That doesn't mean elephants have no understanding or emotional experience of death. In fact, Roy's own research opens up another angle on that question, with the possibility that elephants bury their kin. In a 2024 study, Roy and colleagues documented five cases in India's North Bengal region where baby Asian elephants (Elephas maximus) had been found almost completely buried in muddy drainage ditches at separate sites on tea estates, with only their legs protruding from the soil.

The burials seemed strategic, according to Roy. The trench environment would have enabled the adult elephants to place the infants into the ditch and then scoop earth over their bodies. "The elephants buried the carcasses physically without using any tools," Roy said. "I am as confident as an elephant is in locating water sources and paddy fields. There were elephant footprints all [around] the carcass, and … it's not very difficult for elephants to level the soil over a trench."

Locals in North Bengal and neighboring Assam have found several other burial sites beyond the five Roy and colleagues documented in their paper, and village elders accept elephant burials as established knowledge, he noted. Similar scenarios have been observed in African elephants (Loxodonta), in which dead elephants have been found covered in branches and leaves.

Proops said there could be other explanations for why the calves ended up buried and cautioned that without firsthand observation of the elephants doing so, we can't be sure the burials were intentional.

"I guess the reason we're interested in it is because we want to know whether this shows they understand death," Proops said. "It's very hard to interpret, particularly when it is a rare event. For me, I don't think we can really confirm whether it's a burial, in the sense that it has this sort of cognitive meaning to it."

While questions may linger around this facet of elephant behavior, they show several other intriguing death-related practices. Asian elephants have been observed carrying dead infants for hours or days and are known to stand vigil around the bodies of deceased herd members. Studies also document elephants showing signs of distress when dealing with dead or dying elephants; in Roy's research, the elephants associated with the burials were recorded trumpeting for almost an hour when they were in the area.

"We felt that [they were mourning], but it's always difficult to anthropomorphize such behavior in a natural science journal," Roy said. "Hindu people in India revere elephants as living gods — Shiva and Ganesha — and value elephant subjectivity."

Related: Do animals grieve?

Scientists have also documented several cases in which elephants have turned up at the site of a carcass and interacted with it, curiously touching and sniffing its bones. In fact, this research showed that African elephants that were presented with the bones of several species showed more interest in the skulls and tusks of other elephants of their own species. The finding suggests that they recognize their own species in death, and that judging by the physical signs of excitement the elephants showed in the presence of the bones, that these remains elicit an emotional response, the study authors suggest.

This idea is especially tantalizing because it seems to echo the kind of reflection that humans would show in a graveyard, "a place where the dead reside, and where we actually go out of our way to visit them as well," Proops said. However, the evidence for that conclusion comes up short; in general, the research shows that elephants don't make intentional pilgrimages to commune with these carcasses. Cases where elephants do encounter dead kin seem to occur when they randomly stumble upon a pile of bones; there is no evidence of planned behavior.

"What we really need is GPS data, where we look at normal patterns of movements in the elephants and we see them obviously deviating from those normal routes to go and visit a particular carcass," Proops said.

The truth is that we don't know if elephants understand that they're going to die one day. "There really is no strong evidence that other species do understand that," Proops said.

Two men in New York state have died of a rare fungal lung infection that they caught from bat poop — specifically, poop they were using or planned to use as fertilizer to grow cannabis.

Both men, based in Rochester, shared a love of "Mary Jane" and cultivated their own cannabis plants for personal use. They each developed a condition called histoplasmosis after breathing in spores of a harmful fungus known as Histoplasma capsulatum from bat poop, or guano.

The first man, who was 59-years-old, had purchased guano online to use as fertilizer for his cannabis plants. The other man, 64, was intending to fertilize his cannabis plants with guano he'd found in his attic following a "heavy" bat infestation.

The men developed an array of symptoms from their infections, including fever, chronic cough, extensive weight loss, blood poisoning and respiratory failure. Despite being hospitalized and treated with antifungal medication, both men died of their illnesses, according to a report of their cases, published Dec. 4 in the journal Open Forum Infectious Diseases.

Related: New cause of asthma lung damage revealed

The doctors who treated them said that their deaths should serve as a warning about the potential dangers of using bat guano as a fertilizer for any plants. This may be a particular issue for cannabis growers.

"Given the recent legalization and an expected increase in home cultivation of cannabis, along with the promotion of bat guano for this purpose, it is important to raise public awareness about the potential risk of using bat guano as fertilizer," the case report authors wrote. The authors added that they found numerous articles calling bat guano a "natural superfood" for cannabis plants due to its high concentration of nitrogen and phosphorus.

These recent deadly cases also "emphasize the need for protective measures, such as wearing masks when handling it," the authors added.

Histoplasmosis is a type of pneumonia caused by breathing in spores of H. capsulatum, a fungus found in soil and bird and bat droppings. In the lungs, H. capsulatum spores transform into mature yeast that can spread to other regions of the body via the bloodstream. However, the disease cannot spread between people or between people and their pets.

Each year, around 1 to 2 per 100,000 people in the U.S. are infected with histoplasmosis. Infections mainly occur in the Mississippi and Ohio River valleys, although cases have been reported in 14 states, according to the U.S. Centers for Disease Control and Prevention (CDC).

Only about 1% of people exposed to H. capsulatum develop symptoms. When symptoms do emerge, they usually occur within three to 17 days after exposure, and include fever, chills, muscle aches and chest pain.

People who have had a lung disease prior to being infected and those with weakened immune systems are more likely to develop severe forms of histoplasmosis, which can last for months or longer, and be deadly. Between 5% and 7% of patients hospitalized with histoplasmosis die as a result of their infection.

The men in Rochester had other existing diseases when they caught histoplasmosis, which may have worsened their infections. The first, for instance, had a condition known as emphysema, where the air sacs in the lungs are damaged, which restricts breathing. And both patients had histories of tobacco use, in addition to smoking marijuana.

The authors of the new case report say that commercial fertilizers containing bat guano should be tested for H. capsulatum before being put on the market. If that is not possible, products should be labeled with warning signs and provide instructions on how to use them safely, they said.

To minimize the risk of infection, the CDC additionally recommends that people avoid engaging in activities that may increase their chances of being exposed to H. capsulatum, such as cleaning chicken coops or exploring caves. Large amounts of bird and bat droppings, which may be found in an infested attic, should be removed by professional companies, the agency states.

This article is for informational purposes only and is not meant to offer medical advice.

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Each flu season, about 8% of people in the United States get sick with influenza. Most recover from the sickness, but thousands die annually of seasonal flu. In the last decade, there have been between 21,000 and 51,000 deaths from flu each season, with the exception of 2020-2021 when flu activity was unusually low.

Certain groups are most likely to develop severe flu infections that could lead to death: children under 5, adults 65 and older, people with chronic health conditions and pregnant people.

But how do people actually die of the flu?

There are many ways people can die of the flu. Influenza viruses can inflict serious damage on a range of organs and systems throughout the body, including the lungs, heart, brain and overall immune system, said Dr. Akiko Iwasaki, a professor of immunobiology and molecular, cellular, and developmental biology at Yale University and investigator of the Howard Hughes Medical Institute.

Related: How long is the flu contagious?

These life-threatening complications include pneumonia, which inflames the air sacs of the lungs and can cause them to fill with pus. Flu viruses can directly invade the lungs, causing what's called viral pneumonia. In addition, by damaging cells that line the respiratory tract, the viruses can open the door for bacteria in the body to overgrow, driving inflammation and possibly bacterial pneumonia.

"These are the bacteria that commonly colonize the upper respiratory tract of people without causing any disease," Iwasaki said. After someone gets the flu, these bacteria can gain a foothold in the lungs and multiply.

That's partly because flu viruses make the cells lining the respiratory tract more vulnerable to bacterial penetration and infection, and then "bacteria can proliferate and cause damage more easily," Dr. Octavio Ramilo, chair of the Department of Infectious Diseases at St. Jude Children's Research Hospital, told Live Science.

Severe pneumonia can also cause acute respiratory distress syndrome (ARDS), in which the lungs accumulate fluid, become stiff and can't expand well.

Flu complications don't only affect the lungs, but also the heart. Myocarditis and acute pericarditis respectively inflame the heart's muscles and the sac that surrounds the organ. These conditions can affect the heart's ability to pump blood and disrupt its rhythm, sometimes with deadly consequences.

Flu infections can spark myocarditis because flu viruses inflame and damage the cells that line blood vessels, Ramilo said. The exact cause for pericarditis is unclear, but the tissue typically becomes inflamed following a viral infection like the flu.

Related: Could we ever eradicate the flu?

In rare cases, the flu can also lead to encephalitis, or swelling of the brain. This condition, which is estimated to occur in about 4 in 100,000 children in the U.S. each year, can lead to serious complications including convulsions, coma and death.

Scientists don't know exactly how the flu leads to encephalitis, but a leading hypothesis suggests the infection causes the body to release a flood of cytokines, which are molecules that cause inflammation. These molecules can then enter the brain because the organ's protective barrier has been compromised, potentially by the cytokines themselves. However, more studies are needed to confirm that theory.

Influenza can also lead to sepsis, a life-threatening, body-wide immune response. Flu viruses can trigger this immune reaction on their own, but they can also enable bacteria to enter the bloodstream by breaking down tissues in the body, Ramilo noted. Those bloodborne bacteria can then trigger sepsis. Some studies suggest influenza-associated pneumonia may raise the risk of sepsis up to sixfold, compared to a flu infection without pneumonia; that said, this complication is relatively uncommon overall.

Who is at highest risk of dying from the flu?

A major reason why older adults, young children, people with chronic medical conditions and pregnant people are vulnerable to deadly flu complications is the state of their immune systems.

Older adults experience senescence — essentially biological aging that leads to a decline in cell function that hinders the immune system, Ramilo said. In pregnant people, the immune system lowers its defenses so as not to attack the growing fetus. Thus, people become more vulnerable to flu-related complications during pregnancy, he explained.

Young children's immune systems haven't encountered many germs before. "The immune responses to the [flu] virus have to be developed from scratch," Iwasaki said. Because a child's immune system has no memory of flu viruses, "the virus has the chance to multiply before the immune responses can catch up," she said.

Chronic conditions — such as asthma, kidney disease, HIV/AIDS and cancer — raise the risk of flu complications by compromising either the immune or respiratory system, or both. The flu can also worsen chronic conditions, increasing the risk of death from other causes.

Thankfully, flu vaccines can help prevent severe flu infections and their potentially deadly knock-on effects. For people who do develop severe flu infections, treatments like Tamiflu can dramatically lower the risk of death if provided quickly.

This article is for informational purposes only and is not meant to offer medical advice.

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A test that uses cells from the inside of your cheek may accurately predict the risk of death within the upcoming year, new research hints.

This study, published Oct. 1 in the journal Frontiers in Aging, offers promising support for CheekAge, a new tool that uses cheek — or "buccal" — samples to estimate a person's risk of dying within one year. In a group of adults ages 69 to 101, the test was strongly associated with the risk of death from any cause. A set increase in the study subjects' CheekAge corresponded to a 21% bump in their risk of death within the next 12 months.

CheekAge is a type of epigenetic clock, a tool that measures a person's "biological age" by looking at patterns of chemicals attached to their DNA. In many cases, "biological age is much more telling [about the health of an individual] than the years that they've lived on this planet," said David Furman, an associate professor at the Buck Institute for Research on Aging in Novato, California, who was not involved in the new study.

The long-term hope for tools like CheekAge is to help people slow down or prevent biological aging. But for now, such tools can't tell you how to accomplish that feat, Furman and first study author Maxim Shokhirev, head of computational biology and data science at Tally Health in New York, told Live Science.

Related: Epigenetics linked to the maximum life spans of mammals

What CheekAge does — and what it can't do

In general, epigenetic clocks examine aging of the blood and other tissues to make predictions about a person's chronological age and their risk of death and age-related diseases, like cancer. The most common marker of aging that the clocks look for is DNA methylation, a process by which small molecules called methyl groups attach to DNA over time. These molecules help control gene expression, turning certain genes on and off.

Scientists trained CheekAge using cheek swabs from people ages 18 to 93. They paired patterns of DNA methylation in the cheek cells to an overall score for health, which considered factors such as a person's stress levels, educational and body mass index (BMI). A person's "CheekAge score" was thus tied to their health status and apparent degree of biological aging.

The researchers then determined how accurately CheekAge correlates with one's risk of death. To do so, they looked at volunteers enrolled in the Lothian Birth Cohorts, a long-term research program that tracks aging in participants from childhood through adulthood. In this group of just over 15,000 people, scientists had taken blood samples every three years that could be used to track changes in DNA methylation at roughly 450,000 spots in the genome. Each person's mortality status was taken into account, to tie their epigenetics to their risk of death.

The team then used the epigenetic patterns trained from the cheek on blood data. They found that CheekAge, despite being trained on buccal samples, still showed a strong link to the death risk data drawn from a separate blood dataset that tracked mortality.

"We were surprised to see that CheekAge worked so well in a different tissue," Shokhirev told Live Science in an email. "This may suggest that CheekAge is picking up on health signals that are conserved between different tissue types," he said.

As of yet, CheekAge has been used to look at data retroactively — the researchers knew who lived and died and what their respective epigenetics looked like at the time. Having deduced those patterns, they can now use the tool to estimate living people's risk of death.

"We can't predict if someone will live or die within a year, but we can see an increased or decreased risk of all cause mortality," Shokhirev told Live Science. Further research is needed to determine whether the test can predict other health outcomes, such as the chance of age-related disease.

"One of the primary goals [of making epigenetic clocks] is to identify interventions that can influence or slow down these innate aging mechanisms," Steve Horvath, a professor of human genetics and biostatistics at UCLA who was not involved in the study, told Live Science in an email.

At this point, the tests don't point to any specific treatments, so people should approach them with caution. CheekAge is not available for consumers to purchase, but the same research group has made a similar product, called the TallyAge Test, which is currently on the market. There's a lack of standardization across these commercial epigenetic-clock tests and a risk of misinterpreting the results, said Horvath, who pioneered the first epigenetic clock.

"We understand very little about how to modify an epigenetic landscape," Furman emphasized. He describes epigenetic-clock tests as "moderately useful" to track individuals' behavioral changes, such as in their physical activity or diet, and whether they're tied to epigenetic changes.

"But they [the epigenetic clocks] don't tell you what to do and so there are a lot of limitations on that," Furman said.

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!

People buried in avalanches are more likely to be rescued quickly and survive the experience today than they were four decades ago, a new study suggests.

Avalanches can kill in a number of ways. Most people caught in these snow flows die of injuries sustained during the avalanche, suffocation after being buried by snow, or hypothermia that sets in as they await rescue. Time is critical — most people who live to tell the tale are rescued within the first few minutes after burial.

The first in-depth studies of avalanche survival were published only 30 years ago and focused on incidents in the Swiss Alps. At that time, fewer than half of the people buried in avalanches survived, and almost all of those who did survive had been rescued within 15 minutes of burial.

Since the 1990s, though, we've developed more reliable ways to predict avalanches, as well as new technologies to improve people's chances of being found and rescued quickly. The new research shows that these advancements have improved avalanche survival.

Related: Body of climber missing for nearly 40 years discovered in melting Swiss glacier

The study, published Sept. 25 in the journal JAMA Network Open, examined records of avalanche survival in Switzerland that were published between 1981 and 2020. Within those four decades, more than 7,000 people were caught in avalanches, including 1,643 people who were "critically buried," meaning snow covered their head and chest.

"If a person caught in an avalanche remains on the surface or is only partially buried, with the head and chest exposed, the survival rate exceeds 90%," said Dr. Hermann Brugger, co-author of the study and founder of the Institute for Mountain Emergency Medicine in Bolzano, Italy. That percentage is based on all reports from 1981 to 1998.

"However, when the head and chest are fully buried, survival drops significantly to around 53%," Brugger told Live Science in an email.

The new research shows that, since 1990, the overall avalanche survival rate in Switzerland has increased from 43.5% to 53.4% — that amounts to about 10 more people saved out of every 100 affected.

That survival rate may still sound low, but time makes a big difference. People buried for less than 10 minutes had a 91% chance of survival, but their odds dropped to 76% after just five more minutes. By the 30-minute mark, fewer than 1 in 3 people survive.

"After 10 minutes of burial, the victim begins to suffer from hypoxia (oxygen deprivation) and hypercapnia (buildup of carbon dioxide)," Brugger said. "Exhaled carbon dioxide accumulates in the surrounding snow, reaching toxic levels that are then rebreathed by the victim."

People who are in a group when an avalanche happens can react immediately to locate and dig out their companions, so they can often help within that crucial 10-minute window. Organized rescue teams take longer — but the average time to rescue has fallen from 45 minutes to 25 minutes over the past 40 years, the new study finds.

"Improvements in the survival rate could highlight new medical treatments after extrication or quicker organized rescue give victims a better chance of survival," said Pascal Haegeli, an avalanche risk management expert at Simon Fraser University who was not involved in the study.

The study authors attribute this success to better avalanche safety training for outdoor-sports enthusiasts and new technologies that enable rescuers to find victims faster. This tech includes digital transceivers that broadcast a survivor's location and wearable radar reflectors that can be pinged from handheld detectors or from the air.

Because the study relied on data recorded between 1981 and 2020, some information — especially on how long survivors were buried — was missing. The researchers used statistical methods to help fill in the gaps, but more real-world records are needed to gain additional insight into what makes a difference in avalanche survival.

That said, "these results may not be fully applicable to other regions, because North America experiences higher rates of trauma in avalanche accidents than Europe due to more trees in areas where avalanches occur," said Simon Horton, a researcher and forecaster with Avalanche Canada who was not involved in the study. Other factors, such as changes in snow’s properties over time, may also shape survival trends, he added.

Brugger emphasized that the safest approach is to avoid situations where you might encounter an avalanche in the first place. He suggested carefully reviewing the weather forecast and the current "avalanche danger scale," which uses weather and snow conditions to predict the likelihood of an avalanche — and just how large and dangerous that avalanche might be. Mountaineers should plan their routes accordingly, ensuring that they make adjustments based on the level of avalanche risk in a given area.

"Carry appropriate safety gear, including an avalanche beacon, shovel, probe and possibly an avalanche airbag," which can be deployed during an avalanche to increase a person's size and make them harder to bury, Brugger added. "In the event of an avalanche, the priority is to keep your airway clear by attempting to place your hands over your mouth and nose. And, finally, never go alone."

Editor's note: This article was updated on Oct. 3, 2024, to include quotes from two experts not involved in the research. The story was first published on Oct. 2.

This article is for informational purposes only and is not meant to offer medical or mountaineering advice.

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Four texts that discuss how the samurai carried out Seppuku, a ritual death in which a fellow samurai would usually behead another, have been translated into English for the first time. While the popular imagination often has the samurai stabbing themselves in the stomach and taking their own lives, this rarely happened during the Edo period (1603 to 1868).

The earliest of the four translated texts, named "The Inner Secrets of Seppuku," dates to the 17th century. "This document contains secret teachings that are traditionally only taught verbally, however they have been recorded here so that these lessons will not be forgotten and Samurai can be prepared," wrote Mizushima Yukinari, a samurai who lived between 1607 and 1697, a time when a shogun effectively ruled Japan. While the emperor was technically the ruler of Japan, the shogun held actual political control of the country. During the Edo period, the shoguns were descended from Tokugawa Ieyasu, a warlord who rose to power in Japan and became shogun in 1603.

The texts were translated into English by Eric Shahan, a Japanese translator who specializes in translating martial arts texts and published in the book "Kaishaku: The Role of the Second" (self published, 2024). Shahan also holds a San Dan (third-degree black belt) in Kobudo and has translated many Japanese martial arts texts. In the introduction, Shahan notes that the word "kaishaku" or "second" is a person charged with assisting in the ceremony, and often performed the beheading. The four texts were written to help give instructions to the kaishaku.

The texts described the ceremony, showing how it varied depending on a samurai's rank and which crimes, if any, they were considered to be guilty of. The texts note that it was vitally important that those carrying out the beheading do so correctly, noting that one error in particular could bring about great shame.

"It is essential that you do not fail to notice first the eyes and then the feet of the person committing Seppuku," or the person about to die, reads one of the texts called the "Secret Traditions of Seppuku," written in 1840 by a samurai named Kudo Yukihiro. "If you fail to do this due to a personal connection with the condemned, it will be proof that you have lost your martial bearing and bring down an eternal shame upon yourself."

Related: 7.5-foot-long sword from 4th-century Japan may have 'protected' deceased from evil spirits

While the ceremony varied tremendously, many versions of it involve giving sake (rice wine) to the condemned before a knife was brought on a plate. While the condemned could plunge the knife into themselves, this was often not done. Instead, the texts indicate that the kaishaku would often cut off the condemned person's head shortly after the knife was brought out, Shahan told Live Science in an email.

Shahan noted that the Edo period, the time when two of the texts were written, was one of relative peace in Japan and samurai were not always as skilled with knives and daggers as they had been in earlier times.

In earlier times, when samurai did cut open their own stomachs during Seppuku, they did so in an elaborate way that involved "cutting across the belly, from left to right then, pulling the knife out, repositioning it above the solar plexus and then cutting straight down to make a cross shape before removing the knife and placing it on your right knee," Shahan said. The lower level of skill that samurai tended to have in the Edo period made it difficult for them to perform this properly.

Ranking

A person's rank often dictated how the ceremony was conducted. If the condemned included lords and high-ranking samurai, they would be given the highest level of treatment. A samurai who chose to take their own life when their lord died would also be given the highest level of treatment. People at the highest level would be given some discretion as to how they wanted the ceremony carried out and those conducting it were often of the highest rank and wore a new kamishimo, a formal outfit worn by samurai.

The decapitated heads of high-ranking samurai were likely also treated better after death than those of lower-level warriors. The text written by Yukihiro describes how, at least for high level executions, the hair of the decapitated head should be perfumed afterward and wrapped in a white square cloth before being placed in a box.

Those samurai who were of low rank and considered to have committed the most severe crimes could be given "yondan" — fourth level treatment. This consisted of the condemned being bound and having their head cut off before being tossed into a hole.

While the texts say that a high-ranking samurai should be given better treatment during Seppuku, this may not always have happened.

"The highest-ranking person to commit Seppuku is probably Oda Nobunaga, who committed Seppuku in 1582, after his retainer Akechi Mitsuhide betrayed him and attacked him at Honnoji Temple" in Kyoto, Shahan said.

"Oda was a Daimyo, or lord of one of the hundreds of domains ruled by a powerful Samurai. He had been slowly eliminating his opponents and had succeeded in unifying Japan under his rule when he was betrayed," Shahan said. He chose Seppuku, but "due to the extreme circumstances — he was woefully outmatched, and being overrun — it is unclear how his Seppuku ceremony was conducted," Shahan said. So he may not have had the chance to arrange for an orderly ceremony that included drinking sake or having his hair perfumed after death.

Life and death are traditionally viewed as opposites. But the emergence of new multicellular life-forms from the cells of a dead organism introduces a "third state" that lies beyond the traditional boundaries of life and death.

Usually, scientists consider death to be the irreversible halt of functioning of an organism as a whole. However, practices such as organ donation highlight how organs, tissues and cells can continue to function even after an organism's demise. This resilience raises the question: What mechanisms allow certain cells to keep working after an organism has died?

We are researchers who investigate what happens within organisms after they die. In our recently published review, we describe how certain cells — when provided with nutrients, oxygen, bioelectricity or biochemical cues — have the capacity to transform into multicellular organisms with new functions after death.

Related: Scientists invent 'shape-shifting' antibiotic to fight deadly superbugs

Life, death and emergence of something new

The third state challenges how scientists typically understand cell behavior. While caterpillars metamorphosing into butterflies, or tadpoles evolving into frogs, may be familiar developmental transformations, there are few instances where organisms change in ways that are not predetermined. Tumors, organoids and cell lines that can indefinitely divide in a petri dish, like HeLa cells, are not considered part of the third state because they do not develop new functions.

Xenobots are also able to perform kinematic self-replication, meaning they can physically replicate their structure and function without growing. This differs from more common replication processes that involve growth within or on the organism's body.

Researchers have also found that solitary human lung cells can self-assemble into miniature multicellular organisms that can move around. These anthrobots behave and are structured in new ways. They are not only able to navigate their surroundings but also repair both themselves and injured neuron cells placed nearby.

Taken together, these findings demonstrate the inherent plasticity of cellular systems and challenge the idea that cells and organisms can evolve only in predetermined ways. The third state suggests that organismal death may play a significant role in how life transforms over time.

Postmortem conditions

Several factors influence whether certain cells and tissues can survive and function after an organism dies. These include environmental conditions, metabolic activity and preservation techniques.

Different cell types have varying survival times. For example, in humans, white blood cells die between 60 and 86 hours after organismal death. In mice, skeletal muscle cells can be regrown after 14 days postmortem, while fibroblast cells from sheep and goats can be cultured up to a month or so postmortem.

Metabolic activity plays an important role in whether cells can continue to survive and function. Active cells that require a continuous and substantial supply of energy to maintain their function are more difficult to culture than cells with lower energy requirements. Preservation techniques such as cryopreservation can allow tissue samples such as bone marrow to function similarly to that of living donor sources.

Inherent survival mechanisms also play a key role in whether cells and tissues live on. For example, researchers have observed a significant increase in the activity of stress-related genes and immune-related genes after organismal death, likely to compensate for the loss of homeostasis. Moreover, factors such as trauma, infection and the time elapsed since death significantly affect tissue and cell viability.

Factors such as age, health, sex and type of species further shape the postmortem landscape. This is seen in the challenge of culturing and transplanting metabolically active islet cells, which produce insulin in the pancreas, from donors to recipients. Researchers believe that autoimmune processes, high energy costs and the degradation of protective mechanisms could be the reason behind many islet transplant failures.

How the interplay of these variables allows certain cells to continue functioning after an organism dies remains unclear. One hypothesis is that specialized channels and pumps embedded in the outer membranes of cells serve as intricate electrical circuits. These channels and pumps generate electrical signals that allow cells to communicate with each other and execute specific functions such as growth and movement, shaping the structure of the organism they form.

The extent to which different types of cells can undergo transformation after death is also uncertain. Previous research has found that specific genes involved in stress, immunity and epigenetic regulation are activated after death in mice, zebrafish and people, suggesting widespread potential for transformation among diverse cell types.

Implications for biology and medicine

The third state not only offers new insights into the adaptability of cells. It also offers prospects for new treatments.

For example, anthrobots could be sourced from an individual's living tissue to deliver drugs without triggering an unwanted immune response. Engineered anthrobots injected into the body could potentially dissolve arterial plaque in atherosclerosis patients and remove excess mucus in cystic fibrosis patients.

Importantly, these multicellular organisms have a finite life span, naturally degrading after four to six weeks. This "kill switch" prevents the growth of potentially invasive cells.

A better understanding of how some cells continue to function and metamorphose into multicellular entities some time after an organism's demise holds promise for advancing personalized and preventive medicine.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

Viking age people who lived in what is now Norway were far more likely to be violently killed than Viking age people who lived in Denmark, a new analysis reveals.

The findings were surprising to the research team, as "rates of violence in Viking Age Norway and Denmark were long believed to be comparable," the researchers said in a statement.

For the study, the team compared two groups ofViking Age skeletons: 30 found in Norway and 82 found in Denmark. They found that "11 of the 30 studied Norwegian individuals, or 37 [%], suffered violent deaths, all when being assaulted with bladed and/or pointed weapons," the team wrote in a study published in the September issue of the Journal of Anthropological Archaeology. In Denmark, by contrast, only six individuals — or about 7% — of the people met a violent end, and many of those were executed by hanging or decapitation.

To investigate why more Viking Age people in Norway suffered violent deaths, the team took a deeper look at the archaeological and historical records from that time in Norway and Denmark. The skeletons from Norway are from across the country, although there are no examples from the most northern parts of the country. Many of the skeletons from Denmark come from the eastern or central parts of the country.The date of the skeletons range from the sixth to the 11th centuries. While the exact time frame of the Viking age is debated by scholars it is often dated to around 800-1050, so some of the skeletons used in the study predate the Viking Age.

Historical and archaeological records indicate that Vikings who were killed in raids were buried in the lands they attacked and not brought home, meaning the skeletons in these collections were likely not killed on raids abroad, but were rather killed in their home areas.

Related: What's the farthest place the Vikings reached?

Vikings in Norway were much likelier to be buried with weapons compared with Vikings in Denmark, the team found.

"A notable feature in Norway was the presence of weapons, particularly swords, alongside skeletons in graves," the researchers said in the statement. "The study identified more than 3,000 swords from the Late Iron Age and Viking periods in Norway, with just a few dozen in Denmark. These findings suggest weapons played a significant role in Norwegian Viking identity and social status — further emphasizing the culture's connection to violence."

The team also noted that during the Viking Age, the government in what is now Denmark (an area sometimes called Danmǫrk by the Vikings) seems to have been more centralized than in Norway. Viking Age fortifications in Denmark were larger and more elaborate than those in Norway, the researchers said, suggesting that authorities brought together more people and resources to build them than authorities in Norway could.

In addition, the researchers examined runestones that contain inscriptions in Norway and Denmark. They found that the runestones in Denmark show more evidence of social hierarchy, such as the use of titles.

"More usage of different ranks or even the title 'king' hints at a more stratified society, in which such words were deemed necessary to use," the researchers wrote in the journal article.

The more centralized government in Denmark may have been more successful in limiting violence, the team proposed, and perhaps the violence that did occur often consisted of executions performed by authorities.

While the skeletons were drawn from collections from around Norway and Denmark and dated mostly to the ninth and 10th centuries, it's difficult to know whether they truly reflect the populations they came from, the study authors noted. And though these represent some of the largest bone collections from the Viking Age, the sample size is still relatively small, limiting the conclusions that are possible.

Simon Boas, who wrote a candid account of living with cancer, passed away on July 15 at the age of 47. In a recent BBC interview, the former aid worker told the reporter: "My pain is under control and I'm terribly happy — it sounds weird to say, but I'm as happy as I've ever been in my life."

It may seem odd that a person could be happy as the end draws near, but in my experience as a clinical psychologist working with people at the end of their lives, it's not that uncommon.

There is quite a lot of research suggesting that fear of death is at the unconscious centre of being human. William James, an American philosopher, called the knowledge that we must die "the worm at the core" of the human condition.

But a study in Psychological Science shows that people nearing death use more positive language to describe their experience than those who just imagine death. This suggests that the experience of dying is more pleasant — or, at least, less unpleasant — than we might picture it.

In the BBC interview, Boas shared some of the insights that helped him come to accept his situation. He mentioned the importance of enjoying life and prioritizing meaningful experiences, suggesting that acknowledging death can enhance our appreciation for life.

Despite the pain and difficulties, Boas seemed cheerful, hoping his attitude would support his wife and parents during the difficult times ahead.

Related: What is the key to happiness? We look at the science behind it.

Boas's words echo the Roman philosopher Seneca who advised that: "To have lived long enough depends neither upon our years nor upon our days, but upon our minds."

A more recent thinker expressing similar sentiments is the psychiatrist Viktor Frankl who, after surviving Auschwitz, wrote Man's Search for Meaning (1946) in which he lay the groundwork for a form of existential psychotherapy, with the focus of discovering meaning in any kind of circumstance. Its most recent adaptation is meaning-centered psychotherapy, which offers people with cancer a way to improve their sense of meaning.

How happiness and meaning relate

In two recent studies, in Palliative and Supportive Care and the American Journal of Hospice and Palliative Care, people approaching death were asked what constitutes happiness for them. Common themes in both studies were social connections, enjoying simple pleasures such as being in nature, having a positive mindset and a general shift in focus from seeking pleasure to finding meaning and fulfillment as their illness progressed.

In my work as a clinical psychologist, I sometimes meet people who have — or eventually arrive at — a similar outlook on life as Boas. One person especially comes to mind — let's call him Johan.

The first time I met Johan, he came to the clinic by himself, with a slight limp. We talked about life, about interests, relationships and meaning. Johan appeared to be lucid, clear and articulate.

The second time, he came with crutches. One foot had begun to lag and he couldn't trust his balance. He said it was frustrating to lose control of his foot, but still hoped to cycle around Mont Blanc.

When I asked him what his concerns were, he burst into tears. He said: "That I won't get to celebrate my birthday next month." We sat quietly for a while and took in the situation. It wasn't the moment of death itself that weighed on him the most, it was all the things he wouldn't be able to do again.

Johan arrived at our third meeting supported by a friend, no longer able to grip the crutches. He told me that he had been watching films of him cycling with his friends. He had concluded that he could watch YouTube videos of others cycling around Mont Blanc. He had even ordered a new, expensive mountain bike. "I've wanted to buy it for a long time, but was tightfisted," he said. "I may not be able to ride it, but thought it would be cool to have in the living room."

For the fourth visit, he arrived in a wheelchair. It turned out to be the last time we met. The bike had arrived; he had it next to the couch. There was one more thing he wanted to do.

"If by some miracle I were to get out of this alive, I would like to volunteer in domestic care services — one or two shifts a week," Johan said. "They work hard and it gets crazy sometimes, but they make such an incredible contribution. I wouldn't have been able to get out of the apartment without them."

My experience of patients with life-threatening disease is that it's possible to feel happiness alongside sadness, and other seemingly conflicting emotions. Over a day, patients can feel gratitude, remorse, longing, anger, guilt and relief — sometimes all at once. Facing the limits of existence can add perspective and help a person appreciate life more than ever.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

A man caught a rare but potentially lethal infection after being wounded by wild monkeys in a Hong Kong park and is currently in critical condition, health officials report.

The infection was caused by B virus, which is commonly found in the saliva, urine and stool of macaques, monkeys that live in various locations in the city, according to the Centre for Health Protection (CHP), an agency of the Department of Health in Hong Kong. The monkeys themselves usually are either asymptomatic or show only mild symptoms of infection, the Centers for Disease Control and Prevention (CDC) notes.

According to the infected man's family, he'd encountered the monkeys during a visit to Kam Shan Country Park — home to an area nicknamed "Monkey Hill" — in late February. His case is thought to be the first human infection with B virus in Hong Kong, the CHP noted.

B virus, also called monkey B virus or herpesvirus simiae, rarely infects people. From its discovery in 1932 to 2019, the virus sickened about 50 people, 21 of whom died of the infection, according to the CDC. Most of the affected people had been bitten or scratched by a monkey or were infected when the tissue or bodily fluids of a monkey had made contact with broken skin. There's only one known case of an infected person spreading B virus on to another person, the CDC notes.

Related: 11 (sometimes) deadly diseases that hopped across species

The first known human case of B virus in China was reported in 2021, in a veterinary surgeon in Beijing who'd dissected two dead monkeys and died of the infection about a month later.

In the current case in Hong Kong, the infected 37-year-old man was admitted to Yan Chai Hospital on March 21 "due to fever and decreased conscious level." As of Wednesday (April 3), he was being treated in the intensive care unit. A sample of the fluid that surrounds the brain and spinal cord tested positive for B virus.

The initial symptoms of B virus are flu-like and include fever, chills, muscle ache, fatigue and headache. Additional symptoms include shortness of breath, nausea, vomiting, abdominal pain and hiccups. (Hiccups may potentially be related to the virus invading the nervous system.) People may also develop small blisters on the part of their body a monkey scratched or made contact with.

In its late stages, the infection can cause inflammation of the brain and spinal cord. This can lead to sensations of pain, numbness or itching near the wound site, as well as muscle coordination issues and brain and nerve damage. Breathing problems and death can occur within one day to three weeks after initial symptoms appear, the CDC notes. The infection is typically treated with antiviral drugs and supportive care to maintain a person's vital signs.

Both the CDC and CHP advise the public to stay away from wild monkeys and avoid touching or feeding them. If a person is wounded by a monkey, they should wash the wound and then immediately seek medical attention.

As of April 4, CHP has not released additional information about the ongoing case.

This article is for informational purposes only and is not meant to offer medical advice.

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 total solar eclipse on April 8 could come with an uptick in fatal car crashes, scientists caution in a new report.

It's more common to hear about eclipse-related eye injuries than car crashes. But during the last total solar eclipse in North America — the "Great American Eclipse" of 2017 — the U.S. saw a brief-but-significant increase in fatal crashes, researchers warned in a research letter published Monday (March 25) in the journal JAMA Internal Medicine.

The surge in crashes wasn't tied to the daytime darkness caused by the eclipse. Actually, "we see a significant decrease during the single hour that involves the eclipse," said co-author Dr. Donald Redelmeier, a professor of medicine at the University of Toronto and a staff physician at the Sunnybrook Health Sciences Centre.

"The problem is the surrounding hours, when people are traveling to their place of observation and especially afterwards," Redelmeier told Live Science. "We're especially concerned about the drive home."

Related: Now's the time: Where to buy your solar eclipse glasses before the April 8 total eclipse

During the 2017 eclipse, the path of totality — the route the moon's shadow takes across the Earth below — was narrow, about 70 miles (113 kilometers) wide. In the center of that path, eclipse viewers got the longest glimpse of totality, in which the moon totally blocks the sun's face. Some 20 million people in the U.S. traveled to a different city to reach the path of totality, estimates suggest.

During the upcoming April 8 eclipse, viewers within the path will be able to witness totality for about 2.5 to 4.5 minutes, depending on their location. Viewers outside the path's boundaries will be able to see only a partial eclipse.

Given that the 2017 eclipse generated such heavy traffic, Redelmeier and co-author Dr. John Staples, a clinical associate professor at the University of British Columbia, wanted to see if it was tied to life-threatening road accidents. They pulled data from the National Highway Traffic Safety Administration's Fatality Analysis Reporting System, a registry of all fatal traffic crashes on public roads in the U.S. They focused on the three-day window surrounding the Aug. 21, 2017 eclipse. As points of comparison, they also looked at crash data from three-day windows a week prior to and a week after the astronomical event.

In addition, they used a U.S. Navy calculator to determine the timing of each crash relative to the time of maximal eclipse, based on the accident site's latitude and longitude.

Overall, the eclipse was tied to a 31% increase in fatal crashes, compared to the two comparison time windows. That increase is in line with what's seen around major travel holidays, such as Thanksgiving and July 4th weekend.

Put in other words, around the eclipse, about 10.3 people were involved in fatal crashes per hour, compared with 7.9 people per hour on the comparison days. "This averaged to 1 extra crash-involved person every 25 minutes and 1 extra crash fatality every 95 minutes," the researchers wrote.

The risk varied over time, rising above average before the eclipse, falling below during the eclipse and then shooting up to its highest levels — nearly 50% above average — after the event. The bumps in risk were higher in places with clear skies than in overcast locations, which may be explained by people congregating under clear skies to view the eclipse, Redelmeier said.

In advance of the April 8 eclipse, Redelmeier said, "Our takeaway is to recommend all the standard safety strategies — they really do work." These measures include adhering to speed limits, minimizing distractions while driving, signaling turns and lane changes, and wearing seat belts.

It's worth noting that the new study highlighted only fatal crashes. And while it's likely that the eclipse traffic was also tied to less-severe accidents, "we just don't have the data on that," Redelmeier noted. Nor did the data differentiate between those who traveled to watch the eclipse and those who didn't but were nonetheless caught in eclipse-related traffic.

"Just because you're not an amateur astronomer, doesn't mean you can escape all this," Redelmeier said, "because we all share the roads together."

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!

It's a scene plucked from science fiction: On their deathbed, a person is completely frozen and then stashed away, so that they might be revived in the future. But could it be possible? In this excerpt from "Why We Die: The New Science of Aging and the Quest for Immortality," (Harper Collins, 2024), which was shortlisted for the prestigious 2024 Royal Society Trivedi Science Book Prize, Nobel Prize-winning biologist Venki Ramakrishnan examines the decades-long quest for cryonic preservation — in which people would be frozen at the point of death and defrosted in the future — and the pitfalls of an industry borne out of the idea.

Egyptians mummified their pharaohs so that they could arise corporeally at some point in the future for their journey in the afterworld. Surely now, a few millennia after the pharaohs and with more than a century of modern biology behind us, we would not do anything even remotely so superstitious. But in fact, there is a modern equivalent.

Biologists have long wanted to be able to freeze specimens so that they can store and use them later. This is not so straightforward because all living things are composed mostly of water. When this water freezes into ice and expands, it has the nasty habit of bursting open cells and tissues. This is partly why if you freeze fresh strawberries and thaw them, you wind up with goopy, unappetizing mush.

An entire field of biology, cryopreservation, studies how to freeze samples so that they are still viable when thawed later. It has developed useful techniques, such as how to store stem cells and other important samples in liquid nitrogen. It has figured out how to safely freeze semen from sperm donors and human embryos for in vitro fertilization treatment down the road.

Animal embryos are routinely frozen to preserve specific strains, and biologists' favorite worms can be frozen as larvae and revived. For many types of cells and tissues, cryopreservation works. It is often done by using additives such as glycerol, which allow cooling to very low temperatures without letting the water turn into ice — effectively like adding an antifreeze to the sample. In this case, the water forms a glass-like state rather than ice, and the process should be called vitrification rather than freezing (the word vitreous derives from the Latin root for glass), but even scientists casually refer to it as freezing and the specimens as frozen.

Enter cryonics, in which entire people are frozen immediately after death with the idea of defrosting them later when a cure for whatever ailed them has been found. The idea has been around a long time, but it gained traction through the work of Robert Ettinger, a college physics and math teacher from Michigan who also wrote science fiction. Ettinger had a vision of future scientists reviving these frozen bodies and not only curing whatever had ailed them but also making them young again.

In 1976 he founded the Cryonics Institute near Detroit and persuaded more than 100 people to pay $28,000 each to have their bodies preserved in liquid nitrogen in large containers. One of the first people to be frozen was his own mother, Rhea, who died in 1977. His two wives are also stored there — it is not clear exactly how happy they were to be stored next to each other or their mother-in-law for years or decades to come.

Continuing this tradition of family closeness, when Ettinger died in 2011 at age 92, he joined them. Today there are several such cryonics facilities. Another popular one, Alcor Life Extension Foundation, headquartered in Scottsdale, Arizona, charges about $200,000 for whole-body storage. How do these facilities work? Essentially, as soon as a person dies, the blood is drained and replaced with an antifreeze, and the body is then stored in liquid nitrogen. Theoretically, indefinitely.

Then there are the transhumanists who want to transcend our bodies entirely. But they don't want humanity as we know it to end before we have figured out a way to preserve our minds and consciousnesses indefinitely in some other form. In their view, intelligence and reason may be unique to human beings in the universe (or at least they see no evidence for extraterrestrial intelligence).

Related: Can minds persist when they are cut off from the world?

To them, it is of cosmic importance to preserve our consciousnesses and minds and spread them throughout the universe. After all, what is the point of the universe if there is no intelligence to appreciate it? These transhumanists are content to have only their brains frozen. This takes up less space and costs less. Moreover, it could be faster to infuse the magic antifreeze directly into the brain after death, increasing the odds of successful preservation.

The brain is the seat of memories, consciousness, and reasoning, and that is their sole concern. At some point in the future, when the technology is ripe, the information in the brain will simply be downloaded to a computer or some similar entity. That entity will possess the person's consciousness and memories and will resume "life." It won't be limited by human concerns such as the needs for food, water, oxygen, and a narrow range of temperature. We will have transcended our bodies, with the possibility of traveling anywhere in the universe.

Not surprisingly, transhumanists are generally ardent about space travel, viewing it as our only chance to escape destruction on Earth. One such proponent is business mogul and investor Elon Musk, said to be the wealthiest person in the world, depending on the year, who is well known for his desire to "die on Mars, just not on impact." Presumably one of his first goals upon reaching the red planet will be to construct a cryonics facility.

The bad news is that there is not a shred of credible evidence that human cryogenics will ever work. The potential problems are myriad. By the time a technician can infuse the body, minutes or even hours may have elapsed since the moment of death — even if the "client" moved right next to a facility in preparation.

During that time, each cell in the deceased person's body is undergoing dramatic biochemical changes due to the lack of oxygen and nutrients, so that the state of a cryogenically frozen body is not the state of a live human being. No matter, say cryo advocates: we simply must preserve the physical structure of the brain. As long as it is preserved enough that we can see the connections between all the billions of brain cells, we will be able to reconstruct the person's entire brain.

Mapping all the neurons in a brain is an emerging science called connectomics. Although it has made tremendous advances, researchers are still ironing out the kinks on flies and other tiny organisms. And we don't yet have the know-how to properly maintain a corpse brain while we wait for connectomics to catch up.

Only recently, after many years, has it been possible to preserve a mouse brain, and that requires infusing it with the embalming fluid while the mouse's heart is still beating — a process that kills the mouse. Not one of these cryonics companies has produced any evidence that its procedures preserve the human brain in a way that would allow future scientists to obtain a complete map of its neuronal connections.

Even if we could develop such a map, it would not be nearly enough to simulate a brain. The idea of each neuron as a mere transistor in a computer circuit is hopelessly naive. Much of this book has emphasized the complexity of cells.

Each cell in the brain has a constantly changing program being executed inside it, one that involves thousands of genes and proteins, and its relationship with other cells is ever shifting. Mapping the connections in the brain would be a major step forward in our understanding, but even that would be a static snapshot. It would not allow us to reconstruct the actual state of the frozen brain, let alone predict how it would "think" from that point on. It would be like trying to deduce all of the various aspects of a country and its people, and predict its future development, from a detailed road map.

I spoke to Albert Cardona, a colleague of mine at the MRC (Medical Research Council) Laboratory of Molecular Biology who is a leading expert on the connectomics of the fly brain. Albert stresses that, in addition to the practical difficulties, the brain's architecture and its very nature are shaped by its relationship to the rest of the body.

Related: Extreme longevity: The secret to living longer may be hiding with nuns... and jellyfish

Our brain evolved along with the rest of our body, and is constantly receiving and acting upon sensory inputs from the body. It is also not stable: new connections are added every day and pruned at night when we sleep. There are both daily and seasonal rhythms involving growth and death of neurons and this constant remodeling of the brain is poorly understood.

Moreover, a brain without a body would be a very different thing altogether. The brain is not driven solely by electrical impulses that travel through connections between neurons. It responds also to chemicals both within the brain and emanating from the rest of the body. Its motivation is driven very much by hormones, which originate in the organs, and include basic needs such as hunger but also intrinsic desires. The pleasures our brains derive are mostly of the flesh. A good meal. Climbing a mountain. Exercise. Sex. Moreover, if we wait until we age and die, we would be pickling an old, decrepit brain, not the finely tuned machine of a 25-year-old. What would be the point of preserving that brain?

Transhumanists argue that these problems can be solved with knowledge that mankind will acquire in the future. But they are basing their beliefs on the assumption that the brain is purely a computer, just different and more complex than our silicon-based machines. Of course, the brain is a computational organ, but the biological state of its neurons are as important as the connections between them in order to reconstruct its state at any given time.

In any case, there is no evidence that freezing either the body or the brain and restoring it to a living state is remotely close to viable. Even if I were one of the customers who was sold on cryonics, I would worry about the longevity of these facilities, and even the societies and countries in which they exist. America, after all, is only about 250 years old.

Excerpted from the book WHY WE DIE: The New Science of Aging and the Quest for Immortality by Venki Ramakrishnan. Copyright © 2024 by Venki Ramakrishnan. From William Morrow, an imprint of HarperCollins Publishers. Reprinted by permission.

Intermittent fasting — a dieting strategy that limits when someone can eat each day — has been linked to a 91% higher risk of heart-related death in a large study. This risk was tied to eating in an eight-hour or shorter window in the 24-hour day, compared with a more typical 12- to 16-hour window.

The new, preliminary research was presented March 18 at the American Heart Association (AHA) EPI Lifestyle Scientific Sessions 2024. It looked at deaths from cardiovascular diseases in more than 20,000 U.S. adults, who were followed for an average of eight years.

Experts told Live Science that the study highlights a need to exercise caution around the use of intermittent fasting. However, one noted that, until all the data from the study is published, it's difficult to say whether the time window or types of food consumed are more relevant to a person's risk of death.

"It's quite possible to eat a really low-quality diet while time-restricted eating," Christopher Gardner, professor of medicine at Stanford University, told Live Science. It may also be that some participants with restricted eating windows were facing food insecurity and not eating well or enough, he added. "We don't know everything yet. I'll wait for more," he said of the new research.

Related: 9 heart disease risk factors, according to experts

'There is so much that isn't known'

Intermittent fasting involves eating only during a specific window of time each day, often between four and 12 hours out of 24. Previous research suggests that intermittent fasting improves metrics tied to cardiovascular health in the short term, over a few months, including measures of insulin resistance.

Of the 20,000 people in the new study, 414 reported eating in time windows of eight hours or less each day. Participants were not assigned diets to follow, but rather, their typical diets were assessed through two surveys, in which participants recalled everything they'd eaten in two 24-hour time frames.

The study uncovered a link between eight-hour eating windows and cardiovascular death, but due to its design, it cannot say whether this eating schedule caused the deaths — it shows only a correlation.

"We were surprised to find that compared to people whose eating duration was 12-16 hours … those who restricted their eating time within 8 hours per day had higher risk of cardiovascular death and did not live longer," lead study author Victor Wenze Zhong, professor of epidemiology and biostatistics at the Shanghai Jiao Tong University School of Medicine, told Live Science in an email.

Restricting eating to this short time window was tied to a higher cardiovascular death risk in the overall group and in people with either cancer or heart disease, who were singled out in separate analyses. In addition, participants with existing cardiovascular disease who ate during an eight- to 10-hour window also had a 66% higher risk of dying from heart disease or stroke, compared to those with longer eating windows.

Dr. Wendy Bennett, an associate professor of medicine at Johns Hopkins University School of Medicine, noted that this study suggests a need to scrutinize the "fad diet push that people should be doing time-restricted eating." Bennett and others published research in January 2023 that also raised doubts about the purported benefits of intermittent fasting, suggesting that it's not a successful weight-loss strategy in a six-year time window.

Zhong agreed that the new study calls for more caution regarding intermittent fasting, particularly for people with heart conditions or cancer. Overall, though, "it's too early to give a specific recommendation on [time-restricted eating] based on our study alone." He highlighted the need to explore exactly how eight-hour intermittent fasting might affect heart health and to assess additional populations around the world.

The study does have several limitations. For instance, participants provided dietary data through self-reporting, and some may have incorrectly recalled what they'd eaten. Only two diet surveys were used, so it's unknown whether these accurately represented people's long-term eating habits. The study also didn't consider the nutrient quality of participants' diets or reasons they practiced intermittent fasting.

"It looks tantalizing, but there is so much that isn't known," Gardner said, adding that there is a lot of interest in the study's full results.

Setting the new research aside, intermittent fasting can have other negative consequences, Cynthia Bulik, a psychiatry professor who studies eating disorders at the University of North Carolina School of Medicine, told Live Science in an email. For example, despite it being "hailed as the next great strategy for weight control," intermittent fasting can affect a person's familial and social relationships when their eating schedule doesn't align with that of their loved ones, she noted.

"In addition, for individuals who are genetically predisposed to some eating disorders, prolonged fasting periods could theoretically flip them into negative energy balance (expending more energy than they are consuming)," she said, "and trigger the onset of an eating disorder."

This article is for informational purposes only and is not meant to offer medical advice.

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!

Paul Alexander, an American man who lived in an iron lung for more than 70 years after catching polio, has died at age 78. 

Alexander caught the viral disease when he was 6 years old, in the summer of 1952 when he was living in Texas. The first effective polio vaccine wasn't licensed until 1955. Although many people who catch polio don't show any symptoms, about 1 in 200 become paralyzed for life. Among those with paralysis, between 5% and 10% die because their muscles needed for breathing stop working. 

In Alexander's case, the infection left him paralyzed from the neck down and unable to breathe independently, so doctors put him in an iron lung, which at the time was a state-of-the-art life-support technology that inhales and exhales on the person's behalf. 

Over the next 70 years, Alexander went to college, became a lawyer and published a book about his life, entitled "Three Minutes for a Dog (FriesenPress, 2020)." Alexander's death was announced Tuesday (March 12) on a GoFundMe page organized by Christopher Ulmer, an American disability-rights advocate who met and interviewed Alexander in 2022. 

Related: Polio is spreading in the US for the 1st time in decades. Do you need a booster?

"His story traveled wide and far, positively influencing people around the world," Ulmer wrote on the GoFundMe page. "Paul was an incredible role model that will continue to be remembered." 

Polio, also known as poliomyelitis, is a highly infectious, viral disease that mainly affects children under the age of 5. It is usually transmitted from one person to the next through contact with poop from an infected individual, or less commonly, via the inhalation of droplets, from a person's sneezes or coughs, for example. Once inside the body, poliovirus multiples in the throat and intestines and can sometimes invade the nervous system, leading to paralysis.  

Iron lungs were introduced as a result of epidemics of polio that were taking place in Europe and the U.S. during the first half of the 20th century. The first one was used in 1928 to save the life of an 8-year-old girl at Boston Children's Hospital. 

The devices are large, horizontal cylinders that act as artificial respirators, which work by mimicking the breathing process: air is first sucked out of the box by air pumps that are operated either manually or using a motor. This creates a vacuum that causes the patient's lungs to expand and draw air in. Then, the air is let back into the boxes, increasing the pressure inside and thus deflating the patient's lungs to expel air. 

The first polio vaccine, rolled out in the 1950s, was developed by an American virologist named Jonas Salk. Following this, a global initiative sought to eradicate the disease — to drive the number of cases to zero, permanently — from 1988 onward. 

This effort has driven cases of wild poliovirus down by more than 99% since 1988. Wild poliovirus infections are the most common known form of polio, as opposed to vaccine-derived poliovirus, a rare scenario in which people can become infected with the weakened, live version of the virus included in some shots. (Because of this risk, many countries, including the U.S., no longer use certain polio vaccines.)

There were 350,000 estimated cases of wild poliovirus across more than 125 countries in 1988, but just 6 cases in two countries in 2021. Of the three known types of wild poliovirus, two have been eradicated worldwide: type 2 in 2015 and type 3 in 2019. Type 1 still circulates in Pakistan and Afghanistan.

As polio case numbers have dropped, iron lungs have disappeared from use, with only a handful of people who were already in the devices, like Alexander, still using them. Nowadays, patients who need help to breathe are instead given modern ventilators, which don't require a person to be immobilized in a tube. For example, today, a tube connected to a ventilator may be inserted into a patient's airway or they may wear a face mask connected to such a device. 

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Let's imagine an astronaut suddenly collapses during a spacewalk and dies of cardiac arrest only minutes later.

Thankfully, this has never happened. While 21 people have died in space, spacecraft malfunctions that killed the entire crew, rather than health issues that affected only one person, have been to blame. But if a crewmember did die and others remained, they would have to do something with the body — or else risk contamination as the body began to decay. One option? Release it into space.

Out in the harshness of space, how would a dead body break down? And where could it end up?

Related: How long does it take for a body to decompose?

In the low-pressure vacuum of space, any liquid from the body's surface — the skin, eyes, mouth, ears and lungs — would immediately turn to gas, Jimmy Wu, chief engineer at the Translational Research Institute for Space Health at the Baylor College of Medicine in Texas, told Live Science. Blood vessels near the surface could also rupture and bleed, even after death, Wu added.

The remaining water in the body would likely freeze, Wu said, due to space's low baseline temperature of minus 454.81 degrees Fahrenheit (minus 270.45 degrees Celsius). Liquid loss, plus freezing, could cause a mummified state, essentially preserving the body. "What it might look like is some sort of dehydrated body that's now in space," Wu said.

Any astronaut exposed to space without a spacesuit would meet this fate. What would happen next would depend on if any bacteria were around.

Research on the International Space Station (ISS) has shown that bacteria can survive in space for at least three years. If bacteria were still alive on the body, they would begin to digest it. While most of space is extremely cold, space can also be hot — temperatures on the surface of the ISS can range from minus 328 F to 392 F (minus 200 C to 200 C). In a hotter setting, decomposition would greatly accelerate.

Powerful radiation in space would also likely do a number on the body, breaking apart carbon bonds and causing the skin and muscles to degrade.

After being jettisoned from the spacecraft, the dehydrated and decomposing body would go into orbit, following the direction in which it was pushed out — unless it encountered another object.

With all the space debris and satellites in orbit around Earth, running into one "is actually a risk" a dead body could face, Myles Harris, a doctoral student at the University College London Institute for Risk and Disaster Reduction, told Live Science.

To avoid this risk, NASA recommends going further into space and "leaving planetary orbit" before releasing a body. "It's a hard object, right?" Wu said. A collision between a body and a spaceship or satellite could cause real damage — to both parties.

If the body did avoid collision with satellites and space junk, over time it would slowly be drawn toward Earth by the pull of gravity, especially if the death occurred within low Earth orbit, or about 1,200 miles (2,000 kilometers) or less from Earth. Eventually, in what would probably be the most dramatic part of the cadaver's journey through space, it would reenter the atmosphere and burn up.

Releasing a body from a spaceship isn't the only option after death. Space burial is another possibility, although it comes with the risk of contaminating planetary surfaces. NASA is also developing a body bag that could preserve remains on a spaceship for 48 to 72 hours — plenty of time to return to Earth from the International Space Station. But if trips were far away, like a Mars mission with a seven-month flight back to Earth, crews would have to find other options.

As spaceflights venture farther from Earth, NASA is preparing mission mortality procedures. The commercial spaceflight industry should plan for how to handle death in space too, Wu said.

"Hopefully it never happens, but it might," Harris said. And if it does, it's better to be prepared.

Microbes that lurk in decomposing human corpses could help forensic detectives establish a person's time of death, a new study finds.

The research, published Monday (Feb. 12) in the journal Nature Microbiology, involved placing 36 human cadavers in three locations during spring, summer, fall and winter. The scientists chose locations that were geographically distant from each other — in Tennessee, Texas and Colorado — and that had either a temperate, humid climate or a semiarid climate.

DNA samples were taken from the surface of the cadavers' skin and from the surrounding soil during the first 21 days of decomposition. This is when decomposition rates are generally fast and dynamic, as the tissues quickly begin to break down.

Related: After you die, your microbiome cooperates with soil microbes to 'recycle' your body

In decoding all of the DNA, the scientists revealed that the bodies bore the same profile of microbes regardless of the location, climate or season. Previous studies had identified key members of this profile but were limited to laboratory experiments or to single locations.

"What we ended up finding was a lot of microbes that showed up in every single data set. These were the key decomposers at every environment," Zachary Burcham, first study author and a research assistant professor at the University of Tennessee, told Live Science.

This network of around 20 microbes was made up of a mix of bacteria and fungi that are typically absent from human bodies — that is, until they start decomposing. During the study, the researchers found that these microorganisms appeared in the cadavers like clockwork at specific points during the 21-day decomposition period. This led them to suspect that insects involved in the decomposition cycle, such as blow flies (Calliphora) and carrion beetles, were responsible for introducing these microbes, possibly bringing them over from a previous corpse they visited.

Burcham said they found that, in addition to seeing the same microbes crop up across corpses, they also discovered that the microbes were increasing and decreasing in abundance as time went by,  in a wave-like fashion. By tracking these waves of the different microbes, combining all of the data and using a machine learning model, they found that they could calculate how long a body had been decomposing in a particular area.

"We've given the model the microbial abundances over time, the season, the location,"  Burcham said. "But pretty consistently, it's always been the actual microbial members themselves that the model deems to be the most important. Essentially it will look for these top organisms first and it can get most of the information or predictions from those."

Looking at the microbial community as a whole, the researchers did find variations between the different locations and seasons. However, the microbes that were responding consistently to decomposition always appeared the same, regardless of the external factors. These are the microbes the machine learning model zooms in on, while ignoring the rest.

Related: How long does it take for a body to decompose?

Because their machine learning model could help determine a person's time of death, also referred to as the postmortem interval (PMI), the researchers believe their findings may be useful in forensic investigations across various locations and climates. The results they've obtained so far were found to be highly accurate, give or take three days on each end.

The key members of the newfound microbial decomposer network have been associated with swine, cattle and mouse carcasses in the past, meaning they likely aren't human-specific.

Frederike Quaak, a microbiologist at the Netherlands Forensic Institute (NFI) who was not involved in the study, told Live Science that the findings could become a useful addition to the PMI estimation toolbox. However, she said more research needs to be done for the techniques to actually be used out in the field.

"In real casework, the scenarios would be very different than in their research setting," Quaak said of the new paper. "While they put the bodies on top of the soil, often bodies are being buried, while wrapped in carpets or plastic bags, making them less accessible for insects. Sometimes they are even submerged underwater. So, in these scenarios, the degradation of the body will be very different."

Burcham confirmed that they are now working on new studies investigating the decomposition of organisms within enclosed systems and of buried remains, so they'll be able to see if similar patterns pop up.

"We're working on the basic science, and hopefully someday, we'll see this be useful in a court case," Burcham said.

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A man has died in what is thought to be the first fatal case of Alaskapox, a rare infection caused by a virus in the same broad group as smallpox and mpox.

Many viruses in this group, known as orthopoxviruses, infect both animals and humans, including the camelpox, cowpox and mpox viruses. The Alaskapox virus was first discovered in 2015 in a person in Fairbanks, Alaska, but based on studies conducted in the state's Fairbanks North Star Borough, the virus is thought to primarily infect small mammals, such as red-backed voles (Myodes rutilus) and shrews.

It's suspected that humans pick up the virus from these wild animals, with their pet cats or dogs sometimes acting as intermediaries. While the exact route of transmission is not fully understood, other orthopoxviruses are known to spread through direct contact with skin lesions, so people may get Alaskapox through close contact with infected animals. Human-to-human spread of the disease has never been observed.

Related: Woman gets rare cowpox infection from her pet cat

Since the virus's discovery, five additional people in the Fairbanks area have caught Alaskapox. In these individuals, the pathogen caused a localized rash and swelling of the lymph nodes, but the illnesses resolved on their own.

However, the state's latest case is the first to take place outside the Fairbanks area, in a coastal region called the Kenai Peninsula, and it's the first known case to lead to hospitalization and death.

The patient had a weakened immune system, which likely contributed to the severity of his case, the Alaska Department of Health said in a bulletin released Feb. 9. The case "indicates that AKPV [Alaskapox virus] appears to be more geographically widespread in Alaska's small mammals than previously known and warrants increased statewide awareness among clinicians," department representatives wrote.

Officials from the Alaska Section of Epidemiology (SOE) and the University of Alaska Museum of the North are now working with the Centers for Disease Control and Prevention (CDC) to test more small mammals for the virus outside the Fairbanks region.

The Kenai Peninsula resident who caught Alaskapox lived alone in a forested area and had not traveled prior to developing symptoms in mid-September 2023. However, he was caring for a stray cat that "regularly hunted small mammals and frequently scratched the patient," according to the bulletin.

Samples later taken from the cat came back negative for orthopoxviruses and related antibodies. However, the cat had scratched the man's armpit shortly before he fell ill, and that's where his symptoms began. The man also didn't report any other contact with small mammals, so the cat isn't being ruled out as a possible source of infection, the bulletin notes.

The man's immune system was suppressed as a knock-on effect of cancer treatment, and he noticed a tender, red bump had formed in his right armpit. He visited his primary care doctor and an emergency department several times for evaluation and received various antibiotics. A biopsy of the site eventually conducted on the bump revealed no signs of cancer or bacterial infection there.

As weeks passed, the man grew more fatigued and the pain in his armpit increased and spread to his shoulder. He was hospitalized in mid-November due to presumed cellulitis — a serious bacterial infection — that was impeding the range of motion in his arm.

At the hospital, the man developed a burning pain, which can point to nerve damage. Body scans revealed extensive inflammation of the muscles in his armpit and shoulder. The site where he'd previously had tissue biopsied wasn't healing properly, and it oozed "copious" fluids and was surrounded by gray-colored tissue. "Four smaller pox-like lesions were also present in diffuse locations across his body," the bulletin noted.

The patient was tested for a long list of potential pathogens. One test came up positive for cowpox, but when the sample was sent to an Alaska State Public Health Laboratory, the scientists determined it was some other type of orthopoxvirus. The CDC finally confirmed the virus's identity as Alaskapox, and the analysis revealed that the virus's genetics looked different from those previously found in Fairbanks. That suggests these different Alaskapox viruses aren't very closely related.

The patient was then given several treatments approved for smallpox, and his symptoms began to improve over the course of a week. "However, despite intensive medical support in a long-term care setting, he later exhibited delayed wound healing, malnutrition, acute renal [kidney] failure, and respiratory failure," the bulletin said. The man died in late January 2024.

Officials are now encouraging clinicians across Alaska to familiarize themselves with Alaskapox. They can report suspected Alaskapox cases to the SOE at 907-269-8000, and SOE staff can help facilitate testing.

This article is for informational purposes only and is not meant to offer medical advice.

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An almond-shaped lead bullet — inscribed with the names of Julius Caesar and an unknown city and likely fired from a slingshot — hints that Indigenous people in Spain supported the cause of the would-be dictator during his ultimately successful civil war more than 2,000 years ago, a new study finds. 

As general, Caesar led the Roman army to victory in the Gallic Wars (58 to 50 B.C.). But unwilling to give up his newfound power, he famously crossed the Rubicon River on Jan. 10, 49 B.C., leading his chief political rival, Pompey the Great, to declare Caesar's action tantamount to a state of civil war.

Caesar's civil war (49 to 45 B.C.) spanned Europe, including Italy, Greece, Egypt, Africa, Spain and the Balkan Peninsula. The final engagement, on March 17, 45 B.C., is known as the Battle of Munda, which likely took place in Andalusia, in southern Spain. Tens of thousands of Pompey's troops were killed, and Caesar returned to Rome victorious. 

Now, the analysis of the unique lead projectile is revealing details about the Spanish battles. For example, an inscription on the bullet points to an ancient town never mentioned in historical records of Caesar's civil war, according to the study, published in June 2023 in the journal Zephyrus. 

The artifact is known to specialists as a "glans inscripta" — an inscribed bullet. Measuring 1.8 by 0.8 inches (4.5 by 2 centimeters) and weighing 2.5 ounces (71 grams), the projectile was made using a mold into which molten lead was poured. Engraved on both sides of the mold were letters, resulting in a bullet with raised inscriptions reading "IPSCA" on one side and "CAES" on the other. Part of the projectile was deformed, likely due to impacting a hard object when it was fired in antiquity.

Related: Ancient Roman 'spike defenses' made famous by Julius Caesar found in Germany 

"IPSCA" almost certainly refers to an ancient town that was involved in the civil war between Caesar and Pompey, the researchers argued in their study, but none of the early written sources about the Spanish battles mention Ipsca. Given that the projectile was found near the city of Montilla — the probable location of Munda in Roman times — Ipsca was most likely involved in the last decisive battles of Caesar's civil war, they said.

"In the 1st century BC, many inscribed glandes were made because they were very useful instruments for housing short, very specific messages," study lead author Javier Moralejo Ordax, an assistant professor of archaeology at the Autonomous University of Madrid, told Live Science in an email. The message on this particular projectile was likely meant as political propaganda and encouragement for Caesar's own troops, he said, namely that Ipsca supported Caesar rather than Pompey.

Only one other bullet with Caesar's name on it has been found in Spain. That one, from the province of Jaén, also carries a double inscription. It reads "CAE / ACIPE" — the Latin equivalent of "Suck it, Caesar" — most likely a message from Pompey's troops to their enemy.

Robert Morstein-Marx, a Roman historian at the University of California, Santa Barbara who was not involved in the study, told Live Science in an email that he finds the discovery interesting because, if the authors are correct about the Caesar abbreviation, "this is its first appearance on a bullet used by slingers in his army." The inhabitants of Ipsca, he said, "publicly declared their loyalty to Caesar to those on the other side who had chosen to fight for Pompey's sons."

This tiny bullet gives historians important new information, Moralejo Ordax said, because "most of the indigenous cities were loyal to Pompey and his sons." Ipsca, on the other hand, seems to have been allied with Caesar and "probably manufactured ammunition for Caesar's troops and perhaps provided [slinger] troops for his armies," he said.

In the end, the town of Ipsca may have helped Caesar secure a decisive victory in Spain, setting in motion a chain of events, from his historical appointment as dictator to the fall of the Roman Republic and the eventual rise of the Roman Empire.

People hospitalized for either COVID-19 or the flu face a heightened risk of medical issues, hospital admission and death in the 18 months after they're discharged.

That's according to a new study, published Thursday (Dec. 14) in the journal The Lancet Infectious Diseases, that compared the long-term outcomes for patients sickened with either viral infection. 

Awareness around long COVID — long-term symptoms that persist or newly emerge months to years after an initial COVID-19 infection — has steadily grown since the coronavirus SARS-CoV-2 first appeared. But the new study highlights another significant public health burden: what the study authors informally call "long flu."

Historically, people have thought of viral illnesses like influenza as mostly transient, or "acute," sicknesses. But that idea doesn't account for the impacts that sometimes linger in the "post-acute" phase, said senior study author Dr. Ziyad Al-Aly, a clinical epidemiologist at Washington University in St. Louis and chief of the research and education service at the Veterans Affairs (VA) Saint Louis Health Care System. 

"I think we've ignored this for a long time, and the COVID-19 pandemic kind of put it in the spotlight," Al-Aly told Live Science. As seen with COVID-19, "flu can lead to long-term problems," he said.

Related: When should you get a flu shot? What to know for the 2023-2024 flu season

However, when you compare COVID-19 and the flu head-to-head, the long-term risks tied to a COVID-19 hospitalization are more numerous and more severe than those tied to flu, Al-Aly emphasized, although the flu has more profound effects on the respiratory system, specifically.

"What we saw is that people with COVID-19 had a higher risk of death, hospitalization and sequelae [knock-on effects of disease] than people with the flu," he said. Therefore, "COVID remains a much more serious problem than seasonal influenza." 

For the new study, Al-Aly and colleagues drew information from VA databases to identify people who'd been hospitalized for either COVID-19 or the flu. They included more than 81,000 people who'd been hospitalized for COVID-19 between March 2020 and June 2022, as well as nearly 11,000 people who'd been hospitalized for seasonal flu between October 2015 and February 2019. (The rate of flu hospitalizations was very low between 2020 and 2022, due to precautions taken to reduce COVID-19 spread, so those years weren't included.)

Previous studies have compared the lingering effects of COVID-19 and flu out to about six months post-hospitalization — but the researchers wanted to look further, out to 18 months. 

They looked at the rates of death, hospital admission and intensive care unit (ICU) admission among the study participants, as well as the rates of 94 specific health outcomes related to 10 organ systems. For example, chest pain caused by poor blood flow to the heart (angina) was related to the cardiovascular system, while shortness of breath was related to the respiratory system.

The analysis revealed that the rates of death, medical care and poor health outcomes were "high in both those admitted to hospital for COVID-19 and those admitted to hospital for seasonal influenza," the authors reported. But overall, the risks were substantially higher for those hospitalized with COVID-19.

For every 100 people, the COVID-19 group saw about eight to nine additional deaths within the follow-up period compared with the flu group. Similarly, they experienced about 20 more hospital admissions and eight more ICU admissions per 100 people, compared with the flu group. 

Both COVID-19 and flu came with a risk of various health problems, but COVID-19 affected far more organ systems. COVID-19 was linked to a risk of 64 of the 94 studied symptoms and health conditions, hitting the cardiovascular, neurological and gastrointestinal systems, and more. Influenza was tied to just six: angina, fast heart rate (tachycardia), type 1 diabetes, cough, low blood oxygen and shortness of breath. 

The latter three symptoms tied to flu are related to the respiratory system, and in fact, the flu carried a higher risk of respiratory effects than COVID-19 through the entire follow-up period. This highlights that "flu is more of a respiratory virus, but COVID is more of a multisystemic illness," Al-Aly said.

For all organ systems except gastrointestinal, more than 50% of the health effects occurred more than one month after hospital discharge. This was true for both flu and COVID-19 and highlights the lasting impact both infections can have in the post-acute phase.  

The new study has several limitations. A major one is that it focused only on people hospitalized for either disease. "This is really a major limitation, that we studied it in this context," so more work is needed to understand how the long-term impacts of milder cases of flu and COVID-19 compare to one another, Al-Aly said. In addition, the VA data were heavily skewed toward older male patients, so there are remaining questions as to how these health burdens affect people of other ages and sexes.

With the data at hand, Al-Aly said he hopes the work raises both patients' and health care providers' awareness of the lasting impacts of these diseases.

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! 

Among people with HIV, young children are the likeliest to die while receiving treatment.

This is likely because many children under 5 already have severely weakened immune systems by the time they're diagnosed with HIV, if they are ever diagnosed, according to a Centers for Disease Control and Prevention Morbidity and Mortality Weekly Report (MMWR) published Friday (Dec. 1).

Once on medication, young kids are also more likely than older groups to have interruptions in their treatment. HIV drugs, called antiretroviral therapy (ART), work by driving down the amount of virus in a person's blood until it's undetectable — but if treatment is stopped, viral levels rebound and the infection progresses towards AIDS.

Moreover, young children in low-resource settings, including regions in sub-Saharan Africa, suffer high death rates from other conditions, such as pneumonia and malnutrition, which compound their risk of death with HIV, according to the report.

And these death and treatment-interruption rates "are likely underreported," as children are lost to follow-up and there are inconsistencies in how the data is tracked between locations, the MMWR authors added. Children's HIV services must be prioritized in order to get more kids on consistent ART treatment and avoid preventable deaths, the report concluded.

Related: We could end the AIDS epidemic in less than a decade. Here's how.

It was already known that children under 5 are less likely to receive an HIV diagnosis and be started on ART than older age groups. But less was known about the disparities between young children and older people that are both on ART.

The new report focused on people receiving ART through the United States President's Emergency Plan for AIDS Relief (PEPFAR), a program launched in 2003 to help extinguish the HIV epidemic across the world. PEPFAR currently works in 55 countries in which 78% of people with HIV live, according to the 2023 report from the Joint United Nations Programme on HIV/AIDS (UNAIDS).

The rate of new HIV infections in kids has been falling in these countries, from 287,000 in 2010 to 109,000 in 2022, UNAIDS reported. However, when children do contract HIV, they often don't receive the treatment they need. Globally in 2022, only 57% of the 1.5 million children with HIV received treatment, and an estimated 84,000 died of AIDS-related illnesses. Only 46% of all children with HIV were "virally suppressed," meaning the virus in their blood was undetectable, compared with about 71% of all HIV-positive adults.

The new report looked at people who received ART through PEPFAR between October 2020 and September 2022. That included nearly 18 million people each quarter, including nearly 12,000 infants and 105,000 children ages 1 to 4.

Each year, nearly 5% of the treated infants died, as did 2.5% of the other children under 5. These death rates are many times higher than those in people of older ages, according to the MMWR. Children under 5 were also more likely to have pauses in treatment and less likely to be virally suppressed.

To improve matters, kids must be diagnosed as early as possible and be started on ART immediately after an HIV diagnosis. On this front, there are ongoing global efforts to ensure more children with HIV get tested and onboarded into consistent HIV care that suits their families' needs. Children must simultaneously be protected from other diseases, through vaccinations, for example, and from malnutrition, the MMWR authors noted.

One major challenge is that there are few child-friendly HIV drug formulas, but some recent advancements have helped to overcome that obstacle and make kids' ART easier to maintain.

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The final moments of an adult orca's life have been recorded in what is believed to be the first footage of its kind.

Whale-watchers spotted an orca (Orcinus orca) — a roughly 35-year-old male known to researchers as Hunchy after his hunched back — behaving strangely in waters north of the island of Loppa in Norway on Nov. 6. Two younger orcas huddled close to Hunchy, seemingly holding him at the surface so he could breathe, Pierre Robert de Latour, the author of "Frère des Orques" (Glénat, 2019) who has been diving with orcas in Norway for over 20 years and was on the whale-watching expedition, told Live Science.

The attempt to keep Hunchy afloat seemed "desperate," Robert de Latour said, adding that "it was obvious that he was in trouble."

Robert de Latour got into the water and snorkeled up to the orcas to take a closer look. He noticed the old male looked skinny, and the shape of his belly suggested he hadn't eaten for a long time.

The footage shows Hunchy floating motionless just below the ocean surface after the two younger orcas left the scene. The young pair swam back and forth between Hunchy and a group of orcas further away, Robert de Latour said, repeatedly trying to "activate" the old male.

Related: Orcas sink another boat in Europe after a nearly hour-long attack 

"It's the first time for me seeing something like this. I recognized him — it was very emotional — and then I saw his giant body sinking," Robert de Latour said. "It is said that orcas don't abandon individuals that are in trouble."

The young orcas realized that if they left Hunchy, he would sink to his death, he added. (Orcas can stay submerged for up to 15 minutes, but they usually come to the surface to breathe every minute when resting, and every three to five minutes when traveling.)

But after 50 minutes, they seemingly gave up. "They were helping him until the very last moment," Robert de Latour said.

The footage could be the first time the death of an adult orca has been filmed in the North Atlantic — and possibly worldwide, said Filipa Samarra, a research specialist at the University of Iceland and the founder and principal investigator of the Icelandic Orca Project.

"To my knowledge, the death of an adult member of the group, and how the other [orcas] behave in that instance when an adult is dying, is something that has not been observed before," Samarra told Live Science in an email.

However, researchers have previously recorded the moments surrounding the death of a calf. "We know that orcas show very specific behaviors when calves die," Samarra said. "They have been observed numerous times carrying them, pushing them to the surface, and this can go on for many days." One incident involving orcas from the southern resident population saw a mother carrying her dead calf for over two weeks, she said.

Whether these really were Hunchy's last moments remains to be confirmed. A second boat that arrived on the scene reportedly witnessed the same struggle unfolding one or two hours later, Robert de Latour said, but the crew couldn't determine if Hunchy managed to swim back up to the surface alone or if the younger orcas hauled him up one last time.

"He's probably dead now," Robert de Latour said.

Editor's note: This article previously said the southern resident population saw a mother carrying her dead calf for over two years. It should have said two weeks. This was corrected on Thursday, November 30.

A side-splitting joke might spur, between tears and gasps for air, the age-old exclamation: "I'm dying of laughter!" Although the expression is an obvious exaggeration, is there any truth behind it? Can people actually die of laughter?

Although it's highly unlikely, it's technically possible — and there have been documented cases of laughter-related deaths in the past, doctors told Live Science.

There are a few ways laughter could trigger a negative effect on the body. One of the most vulnerable of these pathways is via the heart. In rare cases, an especially hearty chuckle can cause something called "laughter-induced syncope," a condition that causes a person's blood pressure to drop rapidly during an exaggerated laugh. This triggers a heightened response from the autonomic nervous system — the network of nerves that regulates involuntary physiological processes — leading to a temporary dip in the amount of blood that flows to the brain, which can result in a loss of consciousness.

"When you laugh, you're moving your chest up and down, and it changes the pressure in the thoracic cavity [chest] and it can affect what's called the vagus nerve," which carries signals between the brain and most of the internal organs, Dr. Todd Cohen, chief of cardiology and director of medical device innovation at the New York Institute of Technology, told Live Science. "It can cause you to become lightheaded, [or] even — very, very, very rarely — pass out, especially when it's very exaggerated."

Related: Why do you get dizzy if you stand up too fast?

The first documented case of laughter-induced syncope was in 1997, when a 62-year-old patient with hypertension and other heart-related issues fainted multiple times while roaring with laughter at the television show "Seinfeld," leading to the condition's nickname "the Seinfeld syncope."

The patient did not die from the condition, and this type of syncope usually just causes a person to pass out for less than a few minutes before coming to, Cohen said. Although it is technically possible for laughter-induced syncope to cause the heart to stop, the bigger risk from these fainting spells is that they could happen in dangerous situations, he added.

"It is possible that somebody can have this condition [and] fall and hit their head, or fall down a flight of stairs, or fall off the subway terminal into a train and die," he said, stressing that it's incredibly unlikely.

In other cases, laughter can affect the amount of air that gets to the heart, lungs and brain. For example, high emotions, such as deep amusement, can increase breathing rates and trigger flares of asthma symptoms, which can be further exacerbated by the unusual breathing associated with laughter. In a 2009 study, researchers surveyed 105 patients with asthma and found that more than 40% experienced laughter-induced asthma. In severe cases, asthma attacks can be fatal if someone does not have access to their inhaler.

In theory, laughter could also trigger a sudden spasm of the vocal cords — a condition known as a laryngospasm — or asphyxiation if a person does not get enough oxygen between laughs. But chances of these causes of death are slim, according to Dr. Megan Kamath, a cardiologist at UCLA Health and an assistant clinical professor of medicine at the David Geffen School of Medicine at UCLA.

"While there have been reported cases of death from laughter due to asphyxiation or cardiac arrest, it remains an overall unlikely cause of death for healthy individuals," she told Live Science in an email.

In fact, laughter is harmless — or even beneficial — to your health in the vast majority of situations, Cohen said.

"I think laughter and humor can help [patients] going forward with their condition and put a different perspective on their medical problem and keep them more present in the moments and enjoying life," he said.

Studies show that laughter can reduce anxiety by significantly lowering a person's levels of the stress hormone cortisol while increasing the release of dopamine, the brain's "feel-good" chemical. Additionally, laughing could help increase oxygen flow throughout the body and reduce inflammation in patients with coronary artery disease, according to a not-yet-peer-reviewed study presented at the European Society of Cardiology in Amsterdam in August.

"I believe laughter is the best medicine, and it's very unlikely to kill someone — but it's theoretically possible," Cohen said.

Throughout history, various animals have been associated with death. But why have certain creatures become synonymous with the end of life? Some are known for feasting on the dead, while others have a more nebulous connection to the Grim Reaper. From dragonflies to hornbills, here are seven animals that have been historically associated with death and the afterlife in different cultures.  

Hornbills

The southern ground hornbill (Bucorvus leadbeateri) is a carnivorous bird that hunts for small animals and insects and is found across grassland, savannah and open woodland areas.

The bright-beaked hunters are seen as bringers of death and destruction in nine countries across southern and eastern Africa, according to a 2014 survey of 98 people described in the Journal of Ethnobiology and Ethnomedicine. In general, people considered the southern hornbill to be a bad omen. In Zimbabwe and Malawi, some people thought that a hornbill perching on the roof of a home would bring bad luck to the house's occupants, the study reported. If hornbills are spotted in groups of odd numbers, it is considered a sign of death. In Tanzania, the bird is perceived as a carrier of dead souls and angry spirits. 

Dragonflies

In Japan, red dragonflies (Sympetrum frequens) emerge as adults from low grasslands and migrate up to high mountains to feed. Their abundance grows in the beginning of autumn where they descend from the mountains to breeding grounds at low levels. 

This timing falls perfectly in line with the summer festival of Obon, which celebrates spirits of the dead returning to visit their loved ones. The large red dragonflies were viewed as messengers of these spirits, according to a 1959 ethnographic study.

 Vultures

It's no surprise that vultures make the list of animals associated with death. Vultures use their incredible sense of smell to detect carrion from more than a mile away. And their penchant for circling carcasses while in flight and picking the flesh off from carcasses doesn't help.

Surprisingly, however, in ancient Egypt, the vulture was seen as a symbol of cleanliness within the circle of life and death. According to the Royal Anthropological Institute of Great Britain and Ireland, vultures became the emblem of the deity, Maut, or "the mother of all." Ancient Egyptians may have  believed that all vultures were female and spontaneously born from eggs. This led to the vulture being worn as a headdress by the wives of pharaohs and by female pharaohs for protection. 

Some cultures view vultures as holy ways to dispose of the dead. A Zoroastrian community in India known as the Parsis, as well as Vajrayana Buddhists in Tibet rely on vultures to eat their dead in a practice known as "sky burials," according to the Science History Institute Museum and Library in Philadelphia.

 Bats

In some cultures, bats have long been linked with death.

For instance, the Māori people of New Zealand, associate bats with the hokioi, a mythical nocturnal bird that is said to foretell death. According to The Raupo Book of Maori Proverbs, a common saying was "the bat flies at twilight, the hokioi flies at night." Legend has it that the bird had never been seen, only heard in the night by its screams in the darkness.

It's possible the hokioi was actually a now-extinct bird known as the Haast's eagle (Hieraaetus moorei), a bird of prey that was big enough to have carried off a small child.

 Owls

Owls may be associated with death in part because they are largely nocturnal. In many cultures, they are symbols of death and messengers sent by gods from the underworld, according to the book "Owl" (Reaktion Press, 2009) by Desmond Morris. 

For instance, in Roman mythology, the sound of an owl hooting is a sign of imminent death, according to the book. Owls were believed to have predicted the deaths of several Roman emperors, as their demise followed after the sound of an owl. 

Similar beliefs were discovered during an interview survey conducted in the highlands of the Nyeri District of central Kenya. Seventy-two farmers were interviewed at eight owl territories,  with 2 to 12 interviews conducted per territory. When asked, "What does your ethnic community believe about owls?", 76% of farmers responded by saying that an owl's cry causes death.

 Crows

Carrion Crows (Corvus corone) are highly intelligent birds that eat anything from berries to decaying flesh of dead animals. In Irish folklore, the Badb is one of a trio of war goddesses that took the form of a crow, according to a 19th-century article published in the Proceedings of the Royal Irish Academy. This folklore, the article suggested, said she was able to foreshadow bloodshed, which terrified soldiers on the battlefield. 

 Rats 

Rats are perhaps an unsurprising entry to the list. The rodents carry many pathogens, some of which are deadly. 

For instance, rats were blamed for the 14th-century Black Death, which was caused by the spread of the bacteria Yersinia pestis. Until recently, people thought that rats harbored fleas that carried the pathogen. The plague ultimately killed at least 25 million people in Europe in only five years. 

Studies in recent years, however, suggest that rats were not the primary disease vectors. Rather, humans, and the fleas and body lice they carried, led to most of the disease's spread. 

A large, healthy-looking great white shark that washed up dead on a beach in Canada is the latest in a string of mystery strandings in the region.

The 14-foot-long (4.3 meters) male adult shark was seen thrashing in the water near North Bay Wharf in Nova Scotia before stranding on Broad Cove Beach in Cape Breton on Oct. 5. The carcass then washed back out to sea, but a team with the animal conservation organization Marine Animal Response Society (MARS) managed to recover it a week later for analysis.

Pathologists performed a necropsy on the great white shark (Carcharodon carcharias), but the examination yielded no clues about the cause of death.

"Right now it does not look nutritional (the liver was large and full of lipids), nor does it look like trauma," Laura Bourque, a wildlife pathologist with the Canadian Wildlife Health Cooperative who conducted the necropsy, told Live Science in an email.

Related: Orcas attacked a great white shark to gorge on its liver in Australia, shredded carcass suggests

While the shark's dorsal fin was missing a chunk, the necropsy revealed this was the result of an old, healed injury and probably didn't contribute to the animal's death. The shark was otherwise "in good overall body condition," MARS staff wrote in a Facebook post.

The stranding is the latest in a series of similar incidents that have left scientists floundering. The shark is the fifth great white found beached on the Canadian coast and registered with MARS since last October — a record number when compared to the last 20 years, which saw just one or two such strandings in total, Live Science previously reported.

Scientists haven't got to the bottom of the previous four strandings yet, but they are "in the process of finalizing those cases," Bourque said.

Adult great white sharks rarely wash ashore, Tonya Wimmer, the executive director of MARS, told Live Science in an email. Three of the five dead sharks were juveniles. "This last year has been an anomaly in terms of the number of white sharks reported to us in distress or dead," Wimmer said. 

Very little is known about what causes sharks to become stranded, Wimmer said. While marine mammals can wash up for various reasons — including ingestion of plastics, entanglement in fishing gear, vessel strikes, disease and injury — it's unclear whether the same factors are at play with sharks, she added.

Scientists kept samples of the shark's tissues and are performing additional tests, as "any infectious, toxic or metabolic disease may potentially not be apparent at necropsy," Bourque said.

The team also collected additional samples in the hope they might "support several research projects on these magnificent animals," the Facebook post said.

More than 10 billion snow crabs recently vanished from the Bering Sea, and now we know why: They fell victim to one of the biggest marine heat wave die-offs on record, new research shows.

The deadly heat wave, which struck polar waters between Alaska and Siberia in 2018 and lasted for two years, triggered record-high ocean temperatures and historic declines in sea ice. These "unprecedented" circumstances brought a large population of snow crabs (Chionoecetes opilio) living in the eastern Bering Sea to its knees, according to a new study, published Thursday (Oct. 19) in the journal Science. 

"The collapse of the snow crab population was a strong response to a marine heatwave," researchers wrote in the study. Rather than succumbing directly to warm ocean temperatures, however, it appears the crabs died of starvation.

Snow crabs are small, round-shelled crustaceans that can live for up to 20 years on soft seabeds that are less than 650 feet (200 meters) deep, according to the National Oceanic and Atmospheric Administration (NOAA). The species is closely monitored and managed in the eastern Bering Sea due to its commercial value as seafood.

Related: Why do animals keep evolving into crabs?

Scientists first noticed a dramatic drop in the number of snow crabs during a survey in 2021, which "found the fewest snow crab on the eastern Bering shelf since the survey began in 1975," researchers wrote in the study. No survey was conducted in 2020 due to the coronavirus pandemic, which is why scientists only noticed the crabs had disappeared the following year. But until now, the cause of the population collapse remained a mystery.

It turns out that warm water temperatures caused by the heat wave probably affected the metabolism of the crabs and increased their caloric needs, according to the study. Previous research conducted in a laboratory found that snow crabs' energy requirements doubled when water temperatures rose from 32 degrees to 37.4 degrees Fahrenheit (0 degrees to 3 degrees Celsius). This jump in temperature is equivalent to the change experienced from 2017 to 2018 by juvenile snow crabs, which live in frigid waters known as the "cold pool" and migrate to warmer spots as they mature, according to the study.

Snow crabs' increased caloric needs were reflected by a change in body size between 2017 and 2018, with smaller crabs caught during a survey after the heat wave had begun, according to the study.

The snow crabs also fell victim to bad timing. Right around the time of the heat wave, the crab population in the eastern Bering Sea had boomed, according to the study. The combination of more crabs and higher caloric needs proved deadly.

Other factors — such as predation by Pacific cod (Gadus macrocephalus), cannibalism of smaller crabs by larger ones, fishing and disease — likely contributed to the mortality event, but "temperature and population density were the key variables in the recent collapse," they added. 

The effects of rapidly rising ocean temperatures and more frequent heat waves in response to climate change are difficult to predict, researchers wrote in the study, but the snow crab die-off is "a prime example for how quickly the outlook can change for a population."

And while the future of snow crabs in the eastern Bering Sea is now "precariously uncertain" as they haven't recovered from the mortality event, the population may eventually find refuge in colder waters further north. How the mass death might affect the wider ecosystem remains unclear.

"The problems currently faced in the Bering Sea foreshadow the problems that will need to be confronted globally," the researchers wrote. "The disappearance of snow crab will be a staggering blow to the functioning of some communities in rural Alaska, such as those on St. Paul Island, which rely strongly on the revenue derived from the capture and processing of snow crab."

Orcas have been harassing and toying with porpoises in the Salish Sea for 60 years, often to the point of killing them, but never eating them. Now, researchers think they know why.

The perplexing behavior, dubbed "phocoenacide" or "porpicide," often involves several orcas (Orcinus orca) tossing porpoises (Phocoenidae) around for up to five hours, traumatizing and sometimes killing their plaything.

"I always liken it to a group of friends in a swimming pool and they have a ball between them and the object is to keep the ball above the water," study lead author Deborah Giles, an orca researcher at the University of Washington and research director at the non-profit Wild Orca, told Live Science.

The orcas belong to a small and endangered population called southern resident killer whales that live off the Pacific coast of North America. They are fish-eaters, meaning it's unlikely they are playing with porpoises to consume them — deepening the mystery of why these orcas do it.

Related: Scientists investigate mysterious case of orca that swallowed 7 sea otters whole

"In some cases, you can barely see that there was any interaction," Giles said. "You'll see teeth marks where the [killer] whale was clearly gently holding the animal, but the animal was trying to swim away, so it's scraping the skin."

To find out why the orcas engage in this strange behavior, Giles and her colleagues pored over observational records from 1962 to 2020. Porpicide came and went in waves, Giles said, with orcas engaging in the behavior periodically and ditching it again, sometimes for several years. "It's considered a rare behavior, but when it happens, it's notable," she said.

There are 78 documented cases of southern resident orcas harassing often very young porpoises, with 28 cases resulting in death from "killer whale-induced trauma," the researchers wrote in the study, published Sept. 28 in the journal Marine Mammal Science.

Tossing porpoises around is almost certainly a form of social play, Giles said. But the aim of the game probably isn't to kill, as orcas sometimes continued throwing the porpoises around long after they had died. The activity may strengthen bonds between players and improve coordination and teamwork, according to a statement.

Playing with porpoises could also teach orcas valuable survival skills. Baby harbor porpoises (Phocoena phocoena) and Dall's porpoises (Phocoenoides dalli) are similar in size to the southern residents' favorite food — chinook salmon (Oncorhynchus tshawytscha) — so "it's possible that the whales are using it to learn how to chase fish," Giles said. 

Young orcas and their moms often play with porpoises together, in what could be hunting lessons. " Sometimes they'll let the porpoise swim off, pause, and then go after it," Giles said, which could test and fine-tune the orcas' coordination and prey-handling skills.

Female orcas may also get involved for another reason. Playing with porpoises might be an attempt to provide care for the small mammals, in what is known as a "mismothering behavior," according to the study.

This "might be due to their limited opportunities to care for young" of their own, Giles said in the statement. "Our research has shown that due to malnutrition, nearly 70% of Southern Resident killer whale pregnancies have resulted in miscarriages or calves that died right away after birth."

The southern residents' porpicidal tendencies remain somewhat mysterious, Giles said, but the behavior appears to have spread through the population and across generations over the past 60 years. 

"It is possible that porpoise harassing and killing behavior was spread via social learning," the researchers wrote in the study.

Each human body contains a complex community of trillions of microorganisms that are important for your health while you’re alive. These microbial symbionts help you digest food, produce essential vitamins, protect you from infection and serve many other critical functions. In turn, the microbes, which are mostly concentrated in your gut, get to live in a relatively stable, warm environment with a steady supply of food.

But what happens to these symbiotic allies after you die?

As an environmental microbiologist who studies the necrobiome — the microbes that live in, on and around a decomposing body — I've been curious about our postmortem microbial legacy. You might assume that your microbes die with you — once your body breaks down and your microbes are flushed into the environment, they won’t survive out in the real world.

In our recently published study, my research team and I share evidence that not only do your microbes continue to live on after you die, they actually play an important role in recycling your body so that new life can flourish.

Related: What is the vaginal microbiome?

Microbial life after death

When you die, your heart stops circulating the blood that has carried oxygen throughout your body. Cells deprived of oxygen start digesting themselves in a process called autolysis. Enzymes in those cells — which normally digest carbohydrates, proteins and fats for energy or growth in a controlled way — start to work on the membranes, proteins, DNA and other components that make up the cells.

The products of this cellular breakdown make excellent food for your symbiotic bacteria, and without your immune system to keep them in check and a steady supply of food from your digestive system, they turn to this new source of nutrition.

Gut bacteria, especially a class of microbes called Clostridia, spread through your organs and digest you from the inside out in a process called putrefaction. Without oxygen inside the body, your anaerobic bacteria rely on energy-producing processes that don’t require oxygen, such as fermentation. These create the distinctly odorous-gases signature to decomposition.

From an evolutionary standpoint, it makes sense that your microbes would have evolved ways to adapt to a dying body. Like rats on a sinking ship, your bacteria will soon have to abandon their host and survive out in the world long enough to find a new host to colonize. Taking advantage of the carbon and nutrients of your body allows them to increase their numbers. A bigger population means a higher probability that at least a few will survive out in the harsher environment and successfully find a new body.

A microbial invasion

If you're buried in the ground, your microbes are flushed into the soil along with a soup of decomposition fluids as your body breaks down. They're entering an entirely new environment and encountering a whole new microbial community in the soil.

The mixing or coalescence of two distinct microbial communities happens frequently in nature. Coalescence happens when the roots of two plants grow together, when wastewater is emptied into a river or even when two people kiss.

The outcome of mixing — which community dominates and which microbes are active — depends on several factors, such as how much environmental change the microbes experience and who was there first. Your microbes are adapted to the stable, warm environment inside your body where they receive a steady supply of food. In contrast, soil is a particularly harsh place to live – it's a highly variable environment with steep chemical and physical gradients and big swings in temperature, moisture and nutrients. Furthermore, soil already hosts an exceptionally diverse microbial community full of decomposers that are well adapted to that environment and would presumably outcompete any newcomers.

It's easy to assume that your microbes will die off once they are outside your body. However, my research team's previous studies have shown that the DNA signatures of host-associated microbes can be detected in the soil below a decomposing body, on the soil surface and in graves for months or years after the soft tissues of the body have decomposed. This raised the question of whether these microbes are still alive and active or if they are merely in a dormant state waiting for the next host.

Our newest study suggests that your microbes are not only living in the soil but also cooperating with native soil microbes to help decompose your body. In the lab, we showed that mixing soil and decomposition fluids filled with host-associated microbes increased decomposition rates beyond that of the soil communities alone.

We also found that host-associated microbes enhanced nitrogen cycling. Nitrogen is an essential nutrient for life, but most of the nitrogen on Earth is tied up as atmospheric gas that organisms can't use. Decomposers play a critical role recycling organic forms of nitrogen such as proteins into inorganic forms such as ammonium and nitrate that microbes and plants can use.

Our new findings suggest that our microbes are likely playing a part in this recycling process by converting large nitrogen-containing molecules like proteins and nucleic acids into ammonium. Nitrifying microbes in the soil can then convert the ammonium into nitrate.

Next generation of life

The recycling of nutrients from detritus, or nonliving organic matter, is a core process in all ecosystems. In terrestrial ecosystems, decomposition of dead animals, or carrion, fuels biodiversity and is an important link in food webs.

Living animals are a bottleneck for the carbon and nutrient cycles of an ecosystem. They slowly accumulate nutrients and carbon from large areas of the landscape throughout their lives then deposit it all at once in a small, localized spot when they die. One dead animal can support a whole pop-up food web of microbes, soil fauna and arthropods that make their living off carcasses.

Insect and animal scavengers help further redistribute nutrients in the ecosystem. Decomposer microbes convert the concentrated pools of nutrient-rich organic molecules from our bodies into smaller, more bioavailable forms that other organisms can use to support new life. It's not uncommon to see plant life flourishing near a decomposing animal, visible evidence that nutrients in bodies are being recycled back into the ecosystem.

That our own microbes play an important role in this cycle is one microscopic way we live on after death.

 This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

What happens when we actually die — when our heart stops and all electrical activity "flatlines" in our brain?

Humans have been asking this question since time immemorial. It's a tough one because the dead do not normally ping back to us about the nature of their experiences. Religious texts are capable of supplying a multitude of explanations. But scientists have not given up on providing their own set of answers, and they are making some strides in better understanding the brain's process of transitioning from life to death.

Most recently, this has become possible because of research that has monitored the brains of people who have been in the throes of actually dying. Some of these individuals have been able to report back about what they experienced. According to findings published on Sept. 14 in the journal Resuscitation, the flatlined brains of some cardiac arrest patients burst into a flurry of activity during CPR, even though their heart stopped beating up to an hour. A small subset of study participants who survived were able to recall the experience, and one person was able to identify an audio stimulus that was played while doctors were trying to resuscitate them.

The researchers interpret the brain recordings they made of these patients as markers of "lucid, recalled experiences of death" — an observation that has "never been possible before," says lead author Dr. Sam Parnia, an associate professor of medicine at NYU Langone Health and a longtime researcher of what happens to people as they die. "We've also been able to put forward a coherent, mechanistic explanation for why this occurs."

Related: Surges of activity in the dying human brain could hint at fleeting conscious experiences 

"Recalled experiences of death" — a term Parnia prefers over "near-death experiences" for accuracy — have been reported across diverse cultures throughout recorded history. Some Western scientists previously dismissed such stories as hallucinations or dreams, but recently a few research teams have begun to pay more serious attention to the phenomena as a means to investigate consciousness and shine light on the mysteries of death.

In the new study, Parnia and his colleagues sought to find a biological signature of recalled experiences of death. They teamed up with 25 hospitals, primarily in the U.S. and the U.K. Medical personnel used portable devices that could be placed on the heads of patients who were having a cardiac emergency to measure their brain oxygen levels and electrical activity without interfering with their medical treatment. The researchers also tested for conscious and unconscious perceptions by placing headphones on patients that played a repeated recording of the names of three fruits: banana, pear and apple. In terms of unconscious learning, a person who does not remember hearing these fruit names but is asked to "randomly think of three fruits" may still give the right answer, Parnia says. Past research has shown, for example, that even people in a deep coma can unconsciously learn the names of fruits or cities if those words are whispered in their ear.

Between May 2017 and March 2020, 567 people suffered cardiac arrests at participating hospitals. Medical staff managed to gather usable brain oxygen and activity data from 53 of these patients, most of whom showed an electrical flatline state on electroencephalographic (EEG) brain monitors. But about 40% then experienced electrical activity that reemerged at some point with normal to near-normal brain waves that were consistent with consciousness. This activity was sometimes restored up to 60 minutes into CPR.

Of the 567 total patients, just 53 survived. The researchers conducted interviews with 28 of the survivors. They also interviewed 126 people from the community who had gone through cardiac arrests because the sample size of survivors from the new study was so small. Nearly 40% reported some perceived awareness of the event without specific memories attached, and 20% seemed to have had a recalled experience of death. Many in the latter group described the event as a "moral evaluation" of "their entire life and how they’ve conducted themselves," Parnia says.

In their interviews with survivors, the researchers found that just one person was able to recall the names of fruits that had been played while they received CPR. Parnia acknowledges that this individual could have guessed the correct fruits by chance.

He and his colleagues have developed a working hypothesis to explain their findings. Normally, the brain has "braking systems" in place that filter most elements of brain function out of our experience of consciousness. This enables people to efficiently operate in the world, because under regular circumstances, "you couldn't function with access to your whole brain’s activity being in the realm of consciousness," he says.

In the dying brain, however, the researchers hypothesize that the braking system is removed. Parts that are normally dormant become active, and the dying person gains access to their entire consciousness — "all your thoughts, all your memories, everything that's been stored before," Parnia says. "We don't know the evolutionary benefit of this, but it seems to prepare people for their transition from life into death."

The findings also raise questions about the brain’s resiliency to oxygen deprivation. It could be, Parnia says, that some people who have conventionally been thought to be beyond the point of saving could in fact be revived. "The traditional thinking among doctors is that the brain, once deprived of oxygen for five to 10 minutes, dies," he says. "We were able to show that the brain is quite robust in terms of its ability to resist oxygen deprivation for prolonged periods of time, which opens up new pathways for finding treatments for brain damage in the future."

The new study "represents a Herculean effort to understand as objectively as possible the nature of brain function as it may apply to consciousness and near-death experiences during cardiac arrest," says Dr. Lakhmir Chawla, an intensive care unit physician at Jennifer Moreno Department of Veterans Affairs Medical Center in San Diego, California, who was not involved in the research but has published papers on spikes of EEG activity at the time of death in some patients.

While the results Parnia and his colleagues report are "striking" from a scientific point of view, "I believe that we should allow these data to also inform our humanity," he adds. For one, the findings should "compel clinicians to treat patients who are receiving CPR as if they are awake," which is something "we rarely do."

And for those individuals who do seem to be beyond saving, Chawla says, doctors could invite their families in to come say goodbye, "as the patient may still be able to hear them."

This article was first published at Scientific American. © ScientificAmerican.com. All rights reserved. Follow us on TikTok and Instagram, X and Facebook.

Cancer screening involves searching for signs of the dangerous disease before symptoms develop. The goal is to catch cancer as early as possible, making it easier to treat and thus saving lives. 

A new study recently seemed to cast doubt on whether screening for cancer actually saves lives, but scientists told Live Science we shouldn't jump to conclusions. 

In the new research, published Aug. 28 in the journal JAMA Internal Medicine, scientists reviewed 18 randomized clinical trials (RCTs) involving 2.1 million people, which investigated six tests for four types of cancer: breast, lung, prostate and colorectal, also called colon cancer. The U.S. Centers for Disease Control and Prevention (CDC) supports screening for all of these cancers except prostate cancer, in line with recommendations from an independent panel of experts called the U.S. Preventive Services Task Force (USPSTF). 

The analysis revealed that only one colorectal cancer screening test, known as a sigmoidoscopy — which involves using an endoscope to look at the lower part of the large intestine — appeared to extend people's lives on average, by around three months. 

So does this mean cancer screening doesn't save lives? Not really, because of key limitations in how the study was designed, experts told Live Science.

Related: AI predicts 5-year breast cancer risk better than standard tools — but we aren't sure how it works 

One limitation is that, although the study looked at over 2 million people in total, each individual trial looked at much lower numbers of patients — from around 3,000 in the smallest trial to 400,000 in the largest. 

"In the grand scheme of things, given how many millions of people get screened every year, it's a large study but a small part of the population of people that were looked at," Leigh Jackson, a lecturer in genomic medicine at the University of Exeter in the U.K. who was not involved in the study, told Live Science. Some studies dated as far back as 1989, which may also limit their relevance. 

The authors also studied "all-cause mortality," meaning deaths from any cause, when they looked at whether cancer screening could extend lives. In other words, rather than seeing how many people died from cancer after either being screened for the disease or not, they looked at how many people died of any cause with and without screening. This approach could muddy their interpretation slightly, explained Stephen Duffy, a professor of cancer screening at Queen Mary University of London who was not involved in the research.  

The problem is that "the quite substantial increase in length of life in a very small percentage of people who got cancer is completely swamped by all the deaths from other causes, such as heart disease and strokes," Duffy told Live Science. This means that it may take only a few extra heart attacks in one arm of a trial to "hopelessly bias" the all-cause mortality, he said. (Heart disease is the only disease that causes more deaths in the U.S. each year than cancer.)

However, Jackson said that looking at all-cause mortality may have still been the right thing to do, because if you focus solely on cancer deaths, you may get an inflated sense of how much screening extends life span. Say someone was going to die from cancer at age 70, but screening allowed doctors to detect and treat the disease early and extend their life expectancy to 85. However, if the person then died from a heart attack at 75, they only actually lived for five of those expected 15 years. So if you only consider cancer-related deaths, you might think screening boosts a person's life span more than it does.

While it may be good that the authors used all-cause mortality, they could consider adding other data to their analysis, Jackson said. For example, although RCTs can help assess the effectiveness of screening, Jackson said it would have been good to also use real-world data not collected in a controlled setting like a trial. People who join RCTs tend to be healthier and more affluent at baseline, which can potentially skew their mortality rates, and real-world data could be pulled from much larger groups of people, he said.

So what's the takeaway from the new study?

"I don't think this changes anything," Duffy said. "The well-established experimental evidence that screening for breast cancer, colorectal cancer, lung cancer reduces deaths from these diseases — I think that remains in place." And according to the USPSTF, prostate cancer screening somewhat reduces the risk of death from the disease in some people, but because it's not beneficial for everyone, it's framed as an individual choice that should be discussed with a doctor.   

Saying that cancer screening as a whole is ineffective is the wrong message to give, especially since the study looked at tests for only four types of cancer, Jackson said. "I would hope that the better message would be that there is limited evidence for certain screening tests extending life significantly." 

Notably, the authors didn't consider cervical cancer, for which the CDC and USPSTF recommend screening. 

"You certainly don't want people to look at a finding like this and think, 'Oh, I shouldn't go for my smear test,' or anything like that," Jackson said. "That would be a catastrophic output and totally unsupported by their data."

In the paper, the authors noted that, like any other medical intervention, cancer screening has risks and benefits. There isn't enough data to suggest that screening for some cancers, such as ovarian cancer, reduces deaths from the disease, the USPSTF says. And in some cases, there's not yet enough data to assess whether the benefits outweigh the risks of screening, as is the case with bladder and oral cancer, the task force notes. 

"It is important to consider a person's personal risk for a particular cancer being screened, which is influenced by factors like having a family history of breast cancer or carrying a pathogenic mutation," Dr. Montserrat García-Closas, a professor of epidemiology at The Institute of Cancer Research in the U.K. who was not involved in the research, told Live Science in an email. These factors shift the balance of whether a person would have more risks or benefits from screening, she said. Overdiagnosis and overtreatment of cancer can result in people suffering serious side effects and psychological distress from therapies they may not have needed, she said. 

Although people should be aware of the risks, this doesn't mean they should avoid cancer screening. "People should seek medical advice tailored to their personal circumstances," she said. 

This article is for informational purposes only and is not meant to offer medical advice 

A 2-year-old boy in Nevada has died after being infected with a "brain-eating" amoeba after visiting a natural hot spring in the state. 

In a statement published July 20, the Nevada Division of Public and Behavioral Health (DPBH) announced that the boy — named Woodrow Bundy, according to a Facebook post from his family — was likely exposed to the microbe at Ash Springs in Lincoln County. According to the DPBH, the Centers for Disease Control and Prevention (CDC) confirmed that the child's condition was caused by Naegleria fowleri, a single-cell organism known to cause such brain infections. 

Typically found in soil and warm fresh water, such as lakes, rivers, hot springs and sometimes freshwater spouting from splash pads, the amoeba can cause a rare but deadly infection of the brain, known as primary amebic meningoencephalitis (PAM). 

"If you wind up getting infected with it, chances are you’re going to die," Brian Labus, an epidemiologist and associate professor at the University of Nevada, told FOX5. "Very few people have actually survived this type of infection."

Related: 'Brain-eating' amoeba ruled out in 'cluster of illnesses' in Oklahoma. What could the cause be?

CDC figures show that, of the 154 people known to have been infected by N. fowleri between 1962 and 2021, only four have survived. People typically become infected when water carrying the amoeba enters their nose, likely during swimming or diving, and travels up to the brain via nerves in the nasal cavity. From there, N. fowleri begins to destroy brain tissue, resulting in its nickname as a "brain-eating amoeba." 

"It progresses rather rapidly because it's actively destroying brain tissue, so it's very difficult for your body to deal with something like that and fight it off," Labus told FOX5.

Symptoms of PAM usually begin around five days after exposure to the amoeba, the CDC states, and they can include headaches, fever, nausea or vomiting. At later stages of the disease, victims may experience a stiff neck and confusion and show a lack of attention to people and surroundings, and they may also develop seizures or hallucinations. They may even fall into a coma. Usually, a patient will die around five days after symptoms emerge. 

According to the CDC, young boys like Bundy are at the highest risk of being infected with N. fowleri, compared to other demographics. The reason why is unclear, but the agency suggests this could be because boys more often take part in water activities, such as diving and playing in the sediment at the bottom of lakes and rivers. (The DPBH didn't note whether Bundy was swimming at the time of his exposure or potentially encountered the amoeba some other way.)   

N. fowleri can't be spread from one person to another — it enters the body only through exposure to contaminated water. The DPBH noted that there is "no means to eliminate the ameba from fresh bodies of water," so people should "always assume there is a risk," of exposure, even if that risk is extremely low.

"The only sure way to prevent an infection is to avoid water-related activities in warm fresh water, especially during summer months," the CDC notes. People who choose to swim, however, can reduce their risk of infection by stopping water going up their nose. This could involve avoiding diving, using nose clips or not putting your head under water, the CDC suggests. 

Spaceflight is anything but safe, and the quest to explore the final frontier comes with huge risks for the astronauts leading the charge. But has spaceflight actually cost people their lives?

Yes, 21 people have died in space, Nigel Packham, NASA's associate director of safety and mission assurance, told Live Science. 

Five spaceflight missions — three by NASA and two by the Soviet Union — have ended in fatalities. "The accidents are usually a combination of unusual circumstances, equipment error, human error, politics and management," said Jim Hermanson, a professor of aeronautics and astronautics at the University of Washington in Seattle. 

The two deadliest disasters involved NASA space shuttle missions. In January 1986, space shuttle Challenger exploded 73 seconds into launch, killing its seven-person crew, including Christa McAuliffe, a New Hampshire teacher on board as part of NASA's Teacher in Space Project. The accident was the result of unusually cold temperatures at Cape Canaveral, which caused some of the rocket's sealants to lose flexibility. 

"Hot gas leaked out and burned into the propellant tank and caused a massive explosion," Hermanson told Live Science. Management was also partially to blame, as leadership proceeded with the launch against the warnings of some NASA engineers, he added.

Related: Why does NASA let male astronauts stay in space longer than females?

Another deadly spaceflight accident occurred in February 2003, when space shuttle Columbia broke up during reentry, killing the seven crewmembers. Until the Columbia disaster, "re-entry, descent, and landing were thought to be very benign" parts of spaceflight, Packham said, especially when compared with the extremely violent launch conditions. Columbia sustained damage during launch, when a piece of foam insulation broke off — something that happened during almost every launch before and after Columbia, said Packham, who helped investigate the disaster's cause. But in this case, the foam struck the shuttle's wing, damaging it. The damaged wing couldn't sustain the high temperatures it experienced upon reentry, which caused the ship to disintegrate.

Apollo 1, though it never left the ground, also makes the list of deadly human spaceflight accidents. "I personally don't differentiate between whether or not it happened on the ground," Packham said. After all, the three astronauts on board were setting out for space. But a prelaunch test caused a fire to break out inside the spacecraft, killing the three crewmembers inside. 

Four cosmonauts have also lost their lives in spaceflight. In 1967, the Soviet Union's Soyuz 1 crashed into the ground after a parachute failure, killing the astronaut on board. Politics were partially at fault, as this was the beginning of the space race, and the launch was scheduled to coincide with a political event even though the people involved in the decision knew it wasn't ready, Packham said. The mission control team realized there would be parachute issues as soon as the spacecraft got into orbit, he added.

Three cosmonauts also died in a depressurization accident in 1971. This incident is the only one to actually occur outside Earth's atmosphere, Hermanson said. Generally, "it's ascending and descending — those are the most hazardous parts," he said. The cosmonauts had just spent more than three weeks aboard the first-ever space station established by the Soviet Union. But as they departed for Earth, their spacecraft depressurized, according to NASA. They were not wearing spacesuits. 

These five missions were fatal, but they were not the only ones with the potential to kill or harm the people on board, Packham said. His office keeps a record of the accidents and close calls — and there have been far more than five. 

Today, about 650 people have flown in space, and that number is set to accelerate because of the growing number of commercial spaceflights, Packham said. "It will never be without risk," he said. "That's what it takes to get to space." But understanding the risks involved is essential. That's what Packham's team is working on: collecting data and finding better ways to calculate the exact risk astronauts face. "We have to tell them the chance they make it home," he said.

In their last minutes of life, some people's brains generate a surge of surprisingly organized-looking electrical activity that may reflect consciousness — although scientists aren't entirely sure. 

According to new research, published Monday (May 1) in the journal PNAS, this surge can sometimes occur after a person's breathing stops but before the brain stops functioning. The activity pattern is somewhat similar to what is seen when people are awake or in dreamlike states, leading to speculation that perhaps these electrical surges reflect the otherworldly experiences reported by people who've had close brushes with death: A sense of looking at the body from the outside; a tunnel and white light; or a sense of reliving important memories. 

However, since all the patients in the new study ultimately died, it's impossible to know if they had such experiences. 

"If you talk about the dying process, there is very little we know," said Jimo Borjigin, a neuroscientist at the University of Michigan Medical School who led the study. It's rare for patients to have their brains continuously monitored as they die, Borjigin told Live Science. "This is maybe the first study to really show second-by-second how the brain dies." 

Related: Is brain death reversible? 

Near-death experiences 

Some people who are brought back from the brink of death report seeing or hearing unexplained things during resuscitation or when they seem to be unconscious. The reason for these near-death experiences is unknown, and it's not clear if they're even specific to death. 

International surveys suggest that only about half of what people call "near-death experiences" actually occur in life-threatening situations, said Daniel Kondziella, a neurologist at the University of Copenhagen who was not involved in the new research. The other half occur during meditation or in scary situations that don't endanger one's health or impact the brain's metabolism, Kondiziella told Live Science. 

"The thing is, from the experience itself you cannot say if someone has had a cardiac arrest or syncope [a brief loss of consciousness] or near-miss traffic accident," Kondiziella said. 

Because the people who survive to report a near-death experience are inherently different from the people who die — their brains don't permanently lose function, for one thing — it's hard to determine whether those who actually die also have these subjective experiences. 

In 2013, Borjigin and her colleagues measured electrical activity in the brains of rats that they euthanized via cardiac arrest. They found that for about 30 seconds after the heart stopped, the brain showed a surge in what are called gamma waves, which are the highest-frequency electrical oscillations in the brain. Gamma waves are correlated with conscious experience, but don't necessarily prove that someone is conscious; they're just one of many indicators that someone might be aware and alert. 

In 2022, a separate group of doctors happened to be monitoring the brain of an 87-year-old man with an electroencephalogram (EEG), which detects electrical activity on the surface of the brain, when the man unexpectedly died. Similar to Borjigin's rats, the man's brain showed a surge in gamma activity in the 30 seconds before and after his heart stopped.  

'Reading' the dying brain 

In their new paper, Borjigin and her team made a deliberate effort to use EEG to capture what the brain looks like during death. 

The researchers got permission to monitor dying patients in intensive care whose breathing support had been removed after treatment proved futile. The study included four patients total, all of whom were comatose after cardiac arrest. 

In the 30 seconds to two minutes after their ventilators were removed, two of the four patients' brains showed surges in gamma waves. Interestingly, this gamma activity seemed organized, in that the gamma waves in one portion of the brain were associated with predictable activity patterns in other regions. 

The temporoparietal junction, a brain region where the temporal and parietal lobes meet, toward the back of the brain behind the ear, was particularly active with gamma waves. This region is known to be activated when people have out-of-body experiences or dreams, Borjigin said. 

The new findings echo what was seen in the 87-year-old patient who unexpectedly died, said Raul Vicente, a neuroscientist and data scientist at the University of Tartu who co-authored the 2022 study but was not involved in Borjigin's work. "It's very nice to see a confirmation," he told Live Science. 

"The more consistent findings we have, the more evidence it is that this likely is a mechanism happening at the time of death and if we can pinpoint this down to one location, even better," said Ajmal Zemmar, a neurosurgeon at the University of Louisville Health who also co-authored the 2022 study. 

Zemmar and Vicente are optimistic that these signals could be signs of conscious experience at the moment of death. But reflecting the debate in the field, Kondziella is more skeptical. 

"We know when you die a cardiac death as opposed to a brain death, that takes time," he said. Minutes pass between the heart stopping and brain cells dying, he said. "It shouldn't be a big surprise during those minutes, you will see aberrant electrophysiological activity in the brain." 

Some people may experience something like near-death experiences in these moments, Kondziella said, but we may never know for sure. And again, these experiences may not be unique to death — a more likely explanation for near-death experiences that encompasses both life-threatening experiences and non-life-threatening experiences, he said, may be "REM sleep intrusion into wakefulness," a situation in which the brain blends waking and dreaming states. (REM sleep is marked by dreaming and brain activity patterns that are very similar to waking, including gamma waves and other, lower-frequency waves.) 

Borjigin's team is still collecting end-of-life data, hoping to add to the evidence that the dying brain may generate predictable gamma-wave patterns. Already, other research groups have attempted to use artificial intelligence to identify objects that people saw in their dreams based on their brain activity — similar mind-reading may be possible with unconscious and dying patients, Vicente said. 

"This opens an opportunity at some point, if we gather enough data, to be able to decode what people in different coma states are thinking," Vicente said. 

Sister André, a French nun who held the title of the world's oldest person, died Jan. 17 at age 118 in Toulon, a city in southern France.

Born Lucile Randon on Feb. 11, 1904, she "dedicated most of her life to religious service," according to Guinness World Records. As a young woman, she served as a teacher and later as a governess (private tutor) during World War II. After the war ended, she worked with orphans and the elderly at a hospital in Vichy, France, but it wasn't until 1944, at age 40, that she took vows to become a Catholic nun and changed her name to Sister André.

Guinness World Records declared Sister André not only the world's oldest person but also the oldest nun on record. (She earned the former title in April 2022, after the passing of Kane Tanaka, a 119-year-old Japanese woman.) Sister André was also the oldest person in Europe to survive COVID-19, being released from the hospital in time to celebrate her 117th birthday.

Related: What's the world's oldest civilization?

"I didn't even know that I had it," Sister André told Var-Matin, a French newspaper, in a translated statement. 

For Sister André’s 118th birthday, French President Emmanuel Macron sent her a handwritten birthday card congratulating her on her long life of service — he was the 18th French president to hold office during her lifetime, according to CNN.

While it's easy to speculate what led to her longevity, when pressed, Sister André once chalked it up to her enjoyment of indulging in chocolate and a glass of wine each day. She also told CNN, "I feel I would be better off in heaven, but the good Lord doesn't want me yet."

For anyone hoping to reach a similar age as Sister André, eating high-quality dark chocolate may have a few health benefits, such as protecting against heart failure in women and possibly lowering blood pressure and decreasing the risk of stroke. However, while wine may protect against a few health conditions, such as lowering the risk of heart disease, there isn't much evidence suggesting that it may lead to a longer life.

Sister André was three years shy of earning the title of the oldest person ever to live on record, which is held by Jeanne Louise Calment, a fellow Frenchwoman who died Aug. 4, 1997, at age 122, according to Guinness World Records. 

The moment a person dies, their body begins to break down as cells wither and bacteria invade. But how long does it take for a body to fully decompose? 

Although the process of decomposition starts within minutes of death, there are a number of variables, including the ambient temperature, soil acidity and coffin materials, which can affect how long it takes a body to skeletonize. However, on average, a body buried within a typical coffin usually starts to break down within a year, but takes up to a decade to fully decompose, leaving only the skeleton, Daniel Wescott, director of the Forensic Anthropology Center at Texas State University, told Live Science.

A body buried without a coffin, which doesn't have protection from insects and other elements, typically skeletonizes within five years, according to Nicholas Passalacqua, an associate professor at the Forensic Osteology Research Station at Western Carolina University. 

Decomposition itself is fairly straightforward. Once death occurs and oxygenated blood stops flowing, cells die; in a process called autolysis, cells release enzymes (especially those from the lysosomes, which contain digestive enzymes), which break down the cells themselves, as well as carbohydrates and proteins, according to "The Cell: A Molecular Approach," (Sinauer Associates, 2000). 

Putrefaction, or the decomposition of organic matter without oxygen by bacteria, fungi or other organisms, can turn parts of a body's skin green about 18 hours after death, according to the book "Evaluation of Postmortem Changes" (StatPearls Publishing, 2022). This occurs simultaneously as bacteria in the abdomen rapidly multiply, creating gases that cause the body to bloat and smell. Putrefaction speeds up when the body is in a hot environment, which is why human remains are often kept in refrigerators until it's time for burial. 

Related: What's the deadliest month of the year?

During this bloating stage, the skin can slip and blister and marbling can occur, in which greenish-black blood vessels can be seen through the skin within about 24 to 48 hours of death, according to "Evaluation of Postmortem Change." Eventually, the bloat collapses, and in a process known as black putrefaction, the body's organs and tissues soften, and life forms such as insects and microbes eat the remaining soft tissues, leaving the skeletal remains.

"Decomposition significantly slows down at this [skeletal] stage, and it takes years or decades for the skeletal remains to disintegrate," according to "Evaluation of Postmortem Changes." 

To delay decay, embalmers can drain the blood and other fluids from a corpse and replace it with embalming fluids they inject into the veins. These chemicals, which act as preservatives, stop the bacterial activity that breaks down the body. Although embalming is a common practice, some religions forbid it because it is considered a desecration of the body. 

"If they're embalmed, it can really change things," Wescott told Live Science.

As an example, he pointed to the case of slain civil rights leader Medgar Evers, who was buried in 1963 after being embalmed. When his body was exhumed for evidence in a 1991 murder trial, Wescott said, "his body was so well preserved that they let his son in to see him." 

For those who are embalmed and buried in a coffin, five to 10 years is a more typical decomposition timeline, he said. At that point, the tissue is gone and only bones remain. 

The quality of the embalming job also plays a role, Wescott said. When he exhumed an embalmed body buried 15 years before exhumation, he discovered that it had skeletonized in part because the coffin had broken down. Another embalmed body he exhumed had been buried only a year, and "she looked like she just died, but had some mold growing on her," he recalled. 

Location can have an impact, too. If a casket is buried in acidic soil, it will erode faster, exposing the body to the elements, including insects, which abet the decomposition process. 

There are a few other factors most people don't think about, Wescott said. In an outdoor setting, obese people initially decompose more rapidly in the beginning, but slow down compared with others later in the process because maggots prefer muscle tissue over fat. Chemotherapy and antibiotics used prior to death also can have a huge impact on decay, because both kill off some of the bacteria involved in the process. 

As odd as it sounds, the coffin's liner might also have an influence on the pace of decomposition, Wescott said. Some materials wick fluid away from the body and could cause it to dry out, and even mummify more quickly. If the material holds moisture, the body could become soaked in its own fluids and decompose more quickly.

People die daily from causes ranging from common ailments, such as heart disease, to rare occurrences, such as getting hit by lightning. But during which month do the most deaths happen in the United States?

The deadliest month in the U.S. is the one that heralds the New Year: January. An average of 251,699 people in the U.S. died in January every year between 2010 and 2020, according to a Live Science analysis of the Centers for Disease Control and Prevention (CDC) Wonder database, which tracks how and when people die. In comparison, the averages for the other months for this time period range from 218,102 (August) to 242,475 (December), Live Science found.

Other analyses also find that January is the deadliest month in the U.S. According to an analysis of the CDC Wonder database by The Washington Post, there were 40,000 to 60,000 more fatalities during January than August or September from 1999 to 2014.

Why is January so dangerous? According to the World Health Organization (WHO), the culprit could be the world's most prolific killer: heart disease, a 1999 study in the journal Circulation found, noting that heart conditions were more fatal during the winter months, especially January and February. More body heat is lost during the cold months, so the heart has to work harder, which creates extra stress for people with existing heart conditions, the British Heart Foundation reported. 

Related: What are the most common ways people get injured?

However, that does not completely explain why warmer locales, such as California and Florida, also experienced more deaths in January than during the rest of the year.

Dr. Robert Glatter, an emergency medicine physician at Lenox Hill Hospital in New York City, acknowledged that there has been an ongoing debate about whether the summer or winter is more fatal. Heat-related illnesses are on the rise because of climate change. Young children, older adults and the immunocompromised are the most vulnerable to scorching, humid temperatures. However, despite the increased risk of heatstroke and organ failure during the summer, the winter months are more deadly. Here's why: The flu and other respiratory viruses tend to thrive during the winter.

"In the wintertime, influenza, along with secondary bacterial pneumonia and other typically benign respiratory viruses such as RSV, enterovirus D68, and rhinoviruses" are concerning, Glatter told Live Science in an email. 

The pathogens that cause respiratory infections lurk everywhere during the winter. Closed spaces are germ vectors, breeding bacteria and viruses from too many people being too close together for long stretches of time. Even worse, the flu virus grows a tougher lipid coating during the winter months, according to the University of Southern California’s Verdugo Hills Hospital, and that combined with a more sluggish immune system (another downside of winter) raises the chances of getting sick. The flu still kills millions of people worldwide and 12,000 to 52,000 in the U.S. every year, according to the CDC. Lower respiratory infections, like bronchitis or pneumonia, are the fourth-leading cause of death worldwide, according to the WHO.

But there are myriad other factors that make winter so deadly. "Exposure to extreme cold and wind, lack of adequate heating, older persons living alone, and the use of space heaters, which can lead to fires and carbon monoxide poisoning, are all concerns that make January the deadliest month of the year," Glatter said.

The aftermath of the holiday season also may affect death rates. Overconsumption of food, salt and alcohol adds to physical cardiac stress, along with the psychological stresses that plague what is supposed to be the "most wonderful time of year." But Glatter said that despite the assumption that holiday and post-holiday suicides are the reason for the spike in January deaths, they are not the main causes of death during that month. Generally, the springtime months of April, May and June tend to have the most suicides in the U.S., according to John Hopkins Medicine. 

Deaths from COVID-19 in the past several years have also spiked in the winter. As the U.S. Census database reveals, COVID-19 pushed up death rates in the U.S. by 19% between 2019 and 2020. The U.S. hasn't seen such an upsurge in death rates since the 1918 influenza pandemic about a century ago. Ariel Karlinsky — who researches excess mortality and economics at The Hebrew University of Jerusalem and started the World Mortality Dataset with colleague Dmitry Kobak, who studies COVID-19 excess mortality at Tübingen University in Germany — has been investigating just how much excess mortality there has been worldwide since the pandemic struck. He found that COVID deaths hit a high in January 2020 and 2021.

Glatter is concerned about what could happen as the flu, RSV and COVID-19 flare up in the winter in what he calls a "tripledemic." He urged people to wear a mask to protect against COVID-19, RSV and the flu, especially in spaces without much ventilation. And he had some additional advice as winter approaches.

"Get a flu shot now and a COVID-19 booster if you are not up to date," he said. "And don't forget to wash your hands after contacting people who are ill or coughing. All of these measures can be lifesavers in the long run."

Editor's note: Updated at 9 p.m. EDT Nov. 2 to reflect that the recent surge in RSV may also worsen health outcomes this winter.

A boy in Nevada has died of a rare brain-eating amoeba infection that he likely picked up on the Arizona side of Lake Mead, the Southern Nevada Health District (SNHD) reported Wednesday (Oct. 19). 

"My condolences go out to the family of this young man," Dr. Fermin Leguen, the district's health officer, said in the statement. "While I want to reassure the public that this type of infection is an extremely rare occurrence, I know this brings no comfort to his family and friends at this time."

The brain-eating amoeba Naegleria fowleri lives in soil and warm fresh water, including in lakes, and it causes a rare disease that affects the brain and spinal cord, according to the Centers for Disease Control and Prevention (CDC). The disease, called primary amebic meningoencephalitis (PAM), is nearly always fatal. Between 1962 and 2021, 154 U.S. residents reportedly caught PAM and only four survived. 

People can't become infected by N. fowleri by swallowing the amoeba or interacting with someone with PAM. Rather, people become infected when the microscopic organism gets into their nose and enters the brain via the olfactory nerve, which relays information about smells from the nose to the brain, according to the CDC. Symptoms of the infection emerge between one and 12 days after exposure, and people typically die one to 18 days after symptoms begin. 

Related: Why the 'brain-eating' amoeba is so deadly  

The child, from Clark County, developed symptoms about a week after visiting Lake Mead in early October, according to the SNHD. The earliest symptoms of infection include severe frontal headaches, fever, nausea and vomiting, and later symptoms include stiff neck, seizures, altered mental status, hallucinations and coma, the CDC states.

Overall, PAM remains a very rare disease, and the chances of contracting the infection are extremely low. However, "people should always assume there is a risk for infection whenever entering warm fresh water," the CDC cautions. 

"Attempts have been made to determine what concentration of Naegleria fowleri in the environment poses an unacceptable risk," the CDC states. "However, no method currently exists that accurately and reproducibly measures the numbers of amebae [also spelled amoebae] in the water."

If you're swimming in warm fresh water, the following precautions can help reduce the risk of PAM, according to the CDC:

• Avoid jumping or diving into bodies of warm fresh water, especially during the summer. (In general, N. fowleri can be found in waters from about 80 degrees Fahrenheit (26.6 degrees Celsius) to 115 F (46 C). It grows best at the high end of the range and can survive for short periods at higher temperatures.)
• Hold your nose shut, use nose clips, or keep your head above water when in bodies of warm fresh water.
• Avoid putting your head under water in hot springs and other untreated geothermal waters.
• Avoid digging in, or stirring up, the sediment in shallow, warm fresh water. The amoebae are more likely to live in sediment at the bottom of lakes, ponds, and rivers.

Brain death can be misleading: A person who is brain-dead, meaning they have a complete absence of brain activity, may appear simply comatose, breathing with the help of a ventilator. But is brain death reversible?

Sadly, no: Brain death is permanent. And based on a U.S. law on the books since 1981, it is considered a true death, just as final as death when the heart stops. 

Until the 1950s, the distinction of brain death didn't really exist, because when the heart stopped, the oxygen-starved brain died within a few minutes. Conversely, any direct injury to the human brain severe enough to damage the regions controlling breathing inevitably led the heart and respiration to stop. But the advent of cardiopulmonary resuscitation (CPR), artificial ventilation, and extracorporeal membrane oxygenation (ECMO), which uses a heart-lung machine to oxygenate the blood outside the body, broke that inevitable link. Now, even if the brain is nonfunctional, it's possible to keep the body alive and the other organ systems functioning, at least for a while. 

The rules around diagnosing brain death can differ from place to place, and there are sometimes controversies when a patient's family disagrees with a doctor's assessment that their relative's condition is irreversible or when medical error yields a misdiagnosis. There are also debates about whether brain death should include more tests or criteria. Finally, some faith traditions also object to brain death on religious grounds. But at its core, brain death is defined by doctors as the irreversible loss of all brain function, including in the brain stem.  

How does the brain die? 

Brain death, also known as death by neurological criteria, is a relatively rare way to die, said Dr. Panayiotis Varelas,  chair of neurology at Albany Medical College. But it can happen in cases of severe brain injury, either due to brain trauma or an extended lack of oxygen.

In the face of trauma or a lack of oxygen, the brain cells begin to die, Varelas told Live Science. This mass die-off causes inflammation and swelling, locking the brain into a vicious feedback loop: Damage leads to swelling, which leads to more damage as delicate nerve cells are pressed against the hard case of the skull. The brain stem gets squeezed through the foramen magnum, the hole at the base of the skull where the spinal cord connects to the brain.This damages the regions that control breathing and the heartbeat. Meanwhile, Varelas said, the increasing pressure inside the skull makes it increasingly harder for blood to reach the brain. More and more brain cells die. Once these cells are lost, so are their complex connections to one another, which can lead to irreversible damage.

Once a patient is far along enough on this spiral, brain death is inevitable. In most cases, death of the rest of the body will follow, even if a patient's other organs are still getting oxygen through a ventilator. The other organs stop responding to medical treatment, Varelas said. 

"The whole body shuts down, a sign of how powerful the control of the brain is to the rest of the body," he said. "When the central integrator, the brain, dies, the entire body disintegrates."

Read more: What is brain death? New guidelines offer answers 

How is brain death diagnosed? 

The designation of brain death, however, means that the person can be declared dead before the heart stops beating. This can allow for the removal of artificial life support and futile treatment, or enable organ donation in some cases. An experienced neurologist or neurosurgeon must conduct an examination. To get to that point, a few key criteria must be met: There must be a known cause for the patient's condition, consistent with a catastrophic injury to the whole brain, and the patient's unresponsive state must not be due to side effects of medication, sedation or some other potentially reversible cause, according to a 2022 article in the Journal of Intensive Care.

If these prerequisites are met, the physician can conduct a clinical exam testing for reflexes that depend on a functioning brain stem. There are multiple reflexes tested, such as whether the pupils respond to light and whether the eyelid closes when something touches the surface of the patient's eye. Another test involves flushing the inner ear with cold water. In a patient with a functioning brain stem, the eye will move toward that ear as part of a reflex involving the body's sense of balance. There are also tests involving the gag reflex and other automatic muscle movements. 

If the patient shows no signs of brain stem reflexes, doctors conduct a final test called the apnea test: They remove the patient from mechanical ventilation to see if the person starts breathing spontaneously. A brain-dead patient cannot breath on their own. 

"It's a very, very difficult moment for the families and for us physicians," Varelas said. Brain deaths often occur after sudden medical events or accidents, so the loss of the loved one is often unexpected and extremely difficult to process, he said. 

Doctors can try to reduce swelling in an injured brain and prevent brain death, Varelas said, and they treat patients as aggressively as they can until brain death is declared. But once full brain function is lost, there is no hope for repair.

"That's why they call it the coma dépassé, or 'beyond the coma,'" Varelas said, referring to the name given to the condition by two French neurologists in 1959. "Here we are talking about the loss of function of the entire brain."

Originally published on Live Science

The ancient Egyptians are known for many things, such as mummification, the great pyramid, a sophisticated writing system and a belief in the afterlife. Considering that death and devotion to many deities was featured so prominently in this culture, who was the ancient Egyptian god of death?

While Osiris is often considered the Egyptian god of the underworld or god of the dead, experts told Live Science it's not that simple.

It would be a mistake to call Osiris a god of death, Andrea Kucharek, who directs a project at Heidelberg University in Germany that looks at Osirian ritual texts, told Live Science in an email. "He does not bring or cause death but is sovereign of the dead," Kucharek said. "In fact, he is also very much a god of life, ensuring the fertility of plants, animals and humans."

Ancient Egyptians saw Osiris as a special deity; after he "died," his life was ritually restored.

Related: What did ancient Egypt's pharaohs stash inside the pyramids?

"Osiris was unusual among Egyptian deities since he himself had died and had been restored to life in a new transfigured state thanks to the help of rituals that were performed for him," Mark Smith, a retired professor of Egyptology at the University of Oxford, told Live Science in an email. "Ordinary deceased people in Egypt hoped to undergo the same process of transfiguration and restoration to life using the same rituals that were performed for Osiris, so in a sense, he served as a model for them."

Other Egyptian deities were associated with the dead, such as Anubis, Horus, Hathor and Isis. However, it would also be inaccurate to call any of them a god of death. The jackal-headed Anubis is a particularly important god associated with the dead. He "is the god of embalming," Emily Teeter, an Egyptologist and researcher at the University of Warsaw, told Live Science in an email. In Egyptian mythology, Anubis "performed the very first mummification — of Osiris himself," Laura Ranieri Roy, the founder and director of Ancient Egypt Alive, told Live Science in an email. 

The "ancient [Egyptians] had no death cult, and as a result, they did not worship a god of death," Egyptologist Martin Bommas, director of the Macquarie University History Museum in Australia, told Live Science in an email. 

The closest supernatural being the ancient Egyptians had to a "god of death" might be a scarcely recorded Egyptian deity called "Death, The Great God," John Baines, a professor emeritus of Egyptology at the University of Oxford, told Live Science in an email. "There is an ancient Egyptian god called 'Death, The Great God,' but this god is extremely rarely attested and a malign presence, not a beneficial one."

One of the very few instances in which this enigmatic god is recorded appears on a papyrus that dates to around 3,000 years ago, to the 21st dynasty. This papyrus shows a "winged serpent with two pairs of human legs and a human head, his tail ending in a jackal's head," Françoise Dunand, professor emeritus of history at the University of Strasbourg in France, and Christiane Zivie-Coche, director emeritus of studies at École Pratique des Hautes Etudes, also in France, wrote in their book "Gods and Men in Egypt: 3000 BCE to 395 CE" (Cornell University Press, 2004). 

The writing on the papyrus says this deity is called "death, the great god who makes gods and men," Dunand and Zivie-Coche wrote in their book. It's possible that the person who wrote this papyrus tried to create this "Death, The Great God" but that it never caught on, Dunand and Zivie-Coche noted. 

As a result, while the Egyptians had gods dedicated to the dead and mummification, the idea of a god dedicated to death itself never took on a life of its own. 

Deep in a Tanzanian rainforest in 1972, a famous aging chimpanzee matriarch called Flo breathed her last breath. For her son, Flint, it seemed to be an unbearable loss. The chimp, who was unusually bonded to his mother, suddenly grew listless, losing his appetite and becoming increasingly isolated from the rest of the troop. 

"He ate seldom, and by the end of the third week had lost more than a third of his weight," wrote a young Jane Goodall: The famous primatologist had been a long-time observer of the troop. Then, one month after his mother died, Goodall reported that the emaciated Flint had died, too. 

Researchers have recorded dozens of accounts of strange and heart-rending behaviors like this across the animal kingdom, when an animal's relatives or companions die. These behaviors bring up a compelling question: Do animals grieve and mourn their dead as humans do?

Death rituals

Not too long ago, this might have been dismissed as an unscientific question. But more and more researchers are exploring this idea, and their work falls into a broad field of study called "evolutionary thanatology" — the study of death and its associated rituals. 

Increasingly, this field includes research on behaviors that extend beyond the human realm — such as the case of a female chimp (Pan troglodytes) in Zambia that was observed carefully using a piece of grass to clean the teeth of her recently deceased adopted son, in an almost funereal ritual, according to a 2017 study in the journal Scientific Reports. Or, the account of a Kenyan giraffe (Giraffa camelopardalis rothschildi) that stood vigil over the body of her dead calf even after it had been ravaged by hyenas. 

Related: Which animals sing? 

Similarly, in 2018 many were transfixed by the story of a female orca (Orcinus orca) in the Salish Sea off the coast of Canada and Washington that spent 17 days tirelessly pushing along her lifeless calf, traversing 1,000 miles (1,600 kilometers) with the body before finally letting it go.

It's not just wild animals that display this kind of behavior, but domesticated ones too: Stefania Uccheddu, a veterinarian and researcher at the San Marco Veterinary Clinic and Laboratory in Italy, remembered a case a few years ago when a dog came into her practice for treatment because he refused to eat. "My colleagues took blood samples, they checked the heart — everything was okay. There was no reason to explain why the dog did not eat any more," Uccheddu told Live Science. "The only difference is that his brother had died one week ago." 

This event kick-started Uccheddu's investigation into death-related behaviors in dogs, which resulted in the first study to document a spate of grief-like behaviors in these animals when their canine companions died — including sleeping more, as well as eating and playing less. 

Back in the wild, elephants show some of the most widely documented and striking behaviors around death. African elephants (Loxodonta africana) have been known to tote around the jawbones of their deceased relatives, and to gather in silence for long periods over corpses, almost completely still with their heads dipped downward, and their heavy trunks resting on the ground.

Asian elephants (Elephas maximus) show behaviors that seem similarly mournful. In 2013, elephant biologist Sanjeeta Pokharel found a dead Asian elephant on a riverbank in India, in a spot that was devoid of vegetation. Despite this, the body was mysteriously surrounded by "lots of branches, trees, leaves and everything. That indicates that they might have been brought there," Pokharel told Live Science, who is based at Kyoto University, Japan, and who later described the event in a 2019 study in the journal Primates. She also recounted that two females trekked to the site and walked around the body almost ceremoniously. The somewhat ritualistic scenario reminded her of "a funeral ceremony that happens in Hindu culture where [people] go around the carcass," Pokharel said. "It was exactly like that."

In 2022, she and her co-researcher and husband Nachiketh Sharma, an elephant biologist also based at Kyoto University, published a study in the journal Royal Society Open Science chronicling several death-related behaviors in Asian elephants, crowdsourced from YouTube videos — which including one rarely observed behavior of females doggedly carrying around their dead newborns, draped over their trunks and tusks, for days at a time. 

Related: What's the chattiest animal? 

"Many times, we also got emotional [watching this]," Pohkarel said. In this scenario, "as a human, you can clearly see some kind of grief. [But] I don't know whether we can call it grief right now." 

She described the difficulty at the heart of such research: Researchers lack definitive scientific proof of what these animals are going through, and so there is a risk of anthropomorphizing animals if scientists label it "grief." But by the same token, if researchers don't recognize things that can't be measured, do they risk overlooking a potential wealth of animal emotion? 

What, then, should we call it when a captive dolphin who's lost its companion sinks to the bottom of the pool, sitting there for long stretches and coming to the surface only to breathe? Or the wailing sound a sea lion makes when it loses its young?

Deciphering "grief"

Trying to define these behaviors opens up a can of worms. One school of thought is that in order to grieve, an individual must first be able to understand the concept of death and their relationship with this inevitable force — something that's difficult to prove in animals. (Although, there are some compelling cases that animals do conceptualize death.)

However, a grasp of death may not be necessary for an individual to feel grief. Another way of seeing grief is as part of the process of trying to understand a loss — and therefore observable in how an individual responds to a lifeless corpse. 

It's also true that these behaviors could be ascribed to many other things: curiosity, confusion, stress or fear. This is especially the case in species where the death-response is a little more bizarre. 

Take crows as an example. Death-related behaviors are most frequently recorded in social mammals that form strong bonds with one another, but these birds are a notable exception with their famous "crow funerals." During these events, crows (Corvus brachyrhynchos) gather around the bodies of dead crows in rowdy displays — cawing while examining corpses, and sometimes also attacking and even trying to mate with them. Some researchers suggest that a relative's death may provide an opportunity for these birds to familiarize themselves with the concepts of risk and threat, and to learn about their vulnerabilities from this experience.

Meanwhile, elephants have been observed burying their dead in mud, or covering them with branches and leaves, Sharma said — which, rather than a symbol of mourning, could be a practical attempt to stop a corpse from attracting predators. Similarly, elephants that gather round a corpse seem to be in mourning, but they also sniff and touch the body — so what if instead of pondering their loss, they're simply investigating the cause of death? 

"We can't say whether the elephants are actually curious, or grieving," Sharma said. "It's very difficult to decipher."

Related: Do elephant tusks or rhino horns ever grow back?

How to think about animal grief

Even in humans there's no rulebook for what grief looks like; it manifests in a large and wide-ranging spectrum of behaviors and emotions. So who's to say that curiosity, fear and learning aren't steps in that process for animals, too? 

These jumbled and conflicting views are perhaps what prompted anthropologist Barbara J. King to draw up her own definition of animal grief. The prominent scientist, who wrote a book titled "How Animals Grieve" (University of Chicago Press, 2013), explained that we can define grief by a change in essential functions — a departure from the usual pattern of eating, sleeping and socializing — that is triggered by death. This would widen the net of grief to include dozens of animal species that experience this emotion, King argued.

Some researchers support the idea that grief is valuable for survival, which could also strengthen the case that it occurs in animals. For example, baboons (Papio hamadryas ursinus) that become listless after a relative's death receive increased rates of grooming by other members of the troop, observational research shows.

"Probably this kind of reduction of activity is a way to save energy, attract the attention of your companions, and at the same time create a new network" to replace the one the animal's lost, Uccheddu said. It's not dissimilar to our human world, where communities come together to feed and care for grieving people after a death, she pointed out. 

Meanwhile, more data may eventually bring us closer to understanding what an animal experiences when another one dies. For example, facial recognition technologies are helping researchers track dogs' reactions to life events, Uccheddu explained. Measuring potential shifts in key hormones like oxytocin (thought to play a role in social bonding) could also give us a more precise read on an animal's internal state after it experiences a companion's death, Pokharel added. 

Nevertheless, the question of animal grief is up against a gaping dearth of research on animal cognition and emotion, with complex questions to answer if scientists are ever to definitively prove that animals feel grief. Unless researchers find a way to talk to other species, there's unlikely to be any way to objectively know what they feel. As Sharma said, "only an elephant can say that it's grieving."

Perhaps, though, the ultimate question should be less about whether animal grief exists, and more about how powerful it could be if we acted as though it did. 

Assuming that animals feel attachment to their companions and experience grief-like emotions when they die could have huge welfare implications. It could make us more sensitive to our pets, and help us take better care of animals in zoos. It could also encourage people to care more about humanity's impact on the planet — whether that's poaching, habitat destruction, pollution or climate change — and make a better case for protecting it, for the species we share it with. 

"When we talk about conservation, at least some kind of emotion should be there," Pokharel said. What better way to accomplish that, than to believe that our fellow animals feel it, too? 

Originally published on Live Science.

A new COVID-19 pill cuts the risk of hospitalization or death by 89% when taken within three days of symptom onset, Pfizer recently announced. 

The antiviral pill, PAXLOVID, was given in a placebo-controlled clinical trial to people with COVID-19 who were at high risk of developing severe disease. The pill works by inhibiting an enzyme called a protease, which the virus SARS-CoV-2 needs to keep replicating. 

The drug was so clearly effective that an independent data monitoring committee recommended the trial be stopped so that people in the placebo-arm of the trial could receive the drug. Pfizer plans to submit the data to the Food and Drug Administration (FDA) for emergency use authorization "as soon as possible," according to a statement from the company.

Related: 14 coronavirus myths busted by science

More than 1,200 adults in the U.S. and abroad who tested positive for SARS-CoV-2 and had mild to moderate symptoms were enrolled in the clinical trial.  Participants had at least one underlying condition or characteristic that made them at high risk of developing severe disease. None of the participants were vaccinated, according to The New York Times.  Each participant took either PAXLOVID, in combination with ritonavir (an HIV drug that Pfizer says helps slow the breakdown of the antiviral drug, allowing it to stay in the body for longer), or a placebo pill every 12 hours for five days. 

Out of 389 participants who took PAXLOVID within three days of symptom onset, only three were hospitalized and none died, while out of 385 people who took the placebo within three days, 37 were hospitalized and seven died.

What's more, out of 607 participants who took PAXLOVID within five days of symptom onset (including the people who took the drug within three days), six were hospitalized and none died. Out of 612 who took the placebo within five days of symptom onset, 41 were hospitalized and 10 died. Adverse events were similar between the placebo and the experimental drug groups and most were mild, according to the statement. 

This isn't the first COVID-19 pill to be developed; The FDA is currently reviewing Merck's COVID-19 pill, known as molnupiravir, which the company said cut COVID-19 hospitalizations and deaths by 50% if taken within five days, and which was just approved in the United Kingdom, according to The Associated Press.

PAXLOVID is a modified version of a decades-old drug that was first developed as an intravenous therapeutic during the SARS epidemic, but that now specifically targets SARS-CoV-2 and can be taken as a pill, according to the Times. 

Originally published on Live Science.

Sometimes when ape or monkey infants die, their mothers continue to groom and hold the tiny corpses for days, weeks or months, even as the babies' bodies decay or become mummified. That distressing behavior is more widespread than previously thought, a new study finds.

Researchers recently conducted the first analysis to compare more than 400 documented cases of primate mothers interacting with their dead infants, collecting examples from more than a century of observations covering 50 primate species. The scientists then created "the largest database of primate mothers' responses to their infants' death," they wrote in a new study. 

They also discovered that factors such as the mother's and infant's ages, and the suddenness of the youngster's death could shape a mother's actions toward her infant after it died. 

Related: In photos: Macaque mother cares for mummified corpse of daughter

Scientists have published descriptions of infant corpse-carrying in primates since the early 20th century; one of the first accounts dates to 1915, appearing in the Journal of Animal Behavior, said lead study author Elisa Fernández-Fueyo, a primatologist and graduate student in the Department of Anthropology at the University College London (UCL) in the United Kingdom.

In the 1915 study, primatologist and psychologist Robert Yerkes "reported the case of a captive rhesus macaque mother who carried her dead infant for five weeks," and he suggested in the study that the mother's behavior was a manifestation of maternal instinct, Fernández-Fueyo told Live Science in an email. 

For the new study, the authors analyzed reports dating from 1915 to 2020 of monkeys, apes, bushbabies and lemurs that tended to their deceased young. Roughly 80% of the species they reviewed performed corpse-carrying behavior. However, this activity was most frequently reported in great apes — our closest primate relatives — and Old World monkeys. Both of those primate groups "also carry their infants after death for the longest durations," Fernández-Fueyo said.

For example, in March 2020, researchers described 12 cases of baboon mothers in the wild carrying their dead babies for as long as 10 days. In 2017, a female macaque (a genus of Old World monkey) in an Italian wildlife park carried her dead infant for four weeks, eventually cannibalizing the mummified corpse. And in 2003, after two infant chimpanzees died of respiratory ailments, their mothers carried the babies' corpses for months, Live Science previously reported.

Expressing grief

Lemurs, which diverged from other primate groups more than 60 million years ago, were an exception in the new analysis, and they did not carry deceased infants, Fernández-Fueyo said. However, lemur mothers "were still found to express grief through other behaviors, such as returning to the corpse or giving mother-infant contact calls," Fernández-Fueyo said.

In the species that were reluctant to give up their dead infants, corpse-carrying may occur because the cause of the baby's death isn't visibly obvious (for example, when the baby dies from an illness, rather than from traumatic injury), or when the mother is young and has less direct experience with death than an older female might have, according to the study.

And the length of time that females carried the corpses could indicate the strength of the emotional connection between mother and infant, the authors suggested.

"It is known that the mother-infant bond is regulated by emotions in primates — for example, mother separation from live infants causes anxiety in the mother," Fernández-Fueyo said. In other words, separation anxiety could be a trigger for infant corpse-carrying in primates, and it could explain why the corpses of very young, unweaned infants were typically carried for longer than older babies were, the scientists reported.

In fact, some primate mothers that carried their dead babies would give alarm calls — a sign of stress — if they lost the corpse or if it was taken from them, "suggesting that carrying the corpse may be a way of coping with the stress related with the loss," Fernández-Fueyo said. "More data is needed to further develop our understanding of this, and of how much primate behaviors relating to death may not only be explained by bonds but also by the associated emotions — and, thus, resemble human grief."

The findings were published Sept. 15 in the journal Proceedings of the Royal Society B: Biological Sciences.

Originally published on Live Science.