Ancient DNA suggests Rome’s fall reshaped Europe through gradual migration and intermarriage, not a sudden barbarian takeover.On Tuesday, Google announced AlphaGenome Atlas, a resource that attempts to predict the consequences of every possible single-base variant in the human genome. The human genome is about 3 billion bases long, so trying the other three DNA bases that don't appear in our reference genome means sending a total of 9 billion bases through AlphaGenome software.
AlphaGenome is designed to identify potential functions of non-coding DNA, which does not encode proteins but makes up the vast majority of the human genome. Some of this non-coding DNA is essential for controlling the activity of the protein-coding portion—it tells the cell where and when to make messenger RNAs, how to process them into mature protein-coding forms, and so on. But much of it appears to be little more than the remains of viruses and other molecular parasites.
Being able to identify the functional portion is very useful, as is having all the analysis done by a single software package. But until biologists start to use it heavily (assuming they do), it won't be clear what AlphaGenome offers beyond what we could have gotten out of its training data.
© Vertigo3D
On Tuesday, Google announced AlphaGenome Atlas, a resource that attempts to predict the consequences of every possible single-base variant in the human genome. The human genome is about 3 billion bases long, so trying the other three DNA bases that don't appear in our reference genome means sending a total of 9 billion bases through AlphaGenome software.
AlphaGenome is designed to identify potential functions of non-coding DNA, which does not encode proteins but makes up the vast majority of the human genome. Some of this non-coding DNA is essential for controlling the activity of the protein-coding portion—it tells the cell where and when to make messenger RNAs, how to process them into mature protein-coding forms, and so on. But much of it appears to be little more than the remains of viruses and other molecular parasites.
Being able to identify the functional portion is very useful, as is having all the analysis done by a single software package. But until biologists start to use it heavily (assuming they do), it won't be clear what AlphaGenome offers beyond what we could have gotten out of its training data.
© Vertigo3D
For several decades, paleontologists have described Miracinonyx trumani -- an extinct species of cheetah-like felid that roamed the North American prairies and steppe terrains more than 13,000 years ago -- as North America’s answer to the African cheetah (Acinonyx jubatus).
The post Ancient DNA Rewrites Story of Enigmatic ‘American Cheetah’ appeared first on Sci.News: Breaking Science News.
Researchers have identified more than 1,200 locations in the human genome associated with personality traits, offering the most detailed look yet at the biological underpinnings of traits like sociability, anxiety and curiosity.
The post Scientists Map Genetics of Personality across Million People appeared first on Sci.News: Breaking Science News.
In 2022, when archaeologists uncovered the grave of a young woman buried in 17th-century Pień, Poland, they were confronted with a bizarre scene. Hanging from the big toe of her left foot was an iron padlock. Across her neck lay a large sickle, its blade positioned directly toward her throat.
The strange arrangement suggested that whoever buried her may have feared that, like the vampires of European folklore, she might somehow rise from the grave.
In the four years since “Grave 75” was discovered, scientists have subjected the young woman’s remains, clothing, grave, and the mysterious objects buried with her to an unusually extensive forensic investigation involving ancient DNA, radiocarbon dating, isotope chemistry, X-ray imaging, and microscopic analysis.
Published in the Journal of Archaeological Science: Reports, the findings are beginning to reveal who the mysterious woman was. She was only around 17 to 19 years old when she died, appears to have come from a wealthy or high-status family, and probably spent her childhood in the surrounding region.
Most strikingly, the evidence suggests that local fears surrounding the young woman may have grown after she was already buried.
Researchers believe the padlock was placed on her toe during the first burial. Sometime later, the grave was apparently reopened and the sickle positioned across her neck as an additional safeguard.
The circumstances surrounding the young woman’s death, and why the community apparently feared her enough to take such extraordinary precautions against her trying to return to the land of the living, remain a mystery.
“The burial, uncovered and later disturbed, is distinguished by the co-occurrence of a sickle and a padlock within a single grave, a combination not previously reported in the published archaeological literature,” researchers write. “Ongoing palaeopathological research may shed new light on the cause of death of this young female, which remains a mystery today.”
The grave represents what archaeologists describe as an “anti-demonic” or “anti-vampiric” burial. However, the researchers caution that applying the familiar label of “vampire” to such graves can be misleading.
Although versions of the term vampire can be traced as far back as the Middle Ages, it did not become widespread across Europe until around the 18th century. Earlier Slavic cultures used terms including upiór and strzyga to describe people who, after death, were believed capable of becoming dangerous supernatural beings that could threaten the living.
Researchers have identified several hundred suspected anti-vampire burials dating from the post-medieval period onward across Central and Southeastern Europe.
“Grave 75” was discovered at a cemetery in Pień overlooking the Vistula Valley, where archaeologists have uncovered more than 100 post-medieval graves. Researchers believe the cemetery may have served a Protestant community, and its unusual location away from the village raises the possibility that it was also used to bury people considered social outsiders. Several dozen graves contain unusual features, including deliberately placed stones, coins, sickles, and padlocks.
Sickles and padlocks have both been associated with old European burial practices intended to prevent potentially dangerous dead from returning to harm the living. But finding the two together in one “vampire grave” was unprecedented. No previously published archaeological account had documented a burial containing both a sickle and a padlock.
The woman lay on her back with her legs extended. Around her neck was a 14-inch-long serrated sickle, positioned with its cutting edge toward her throat. Hanging from the big toe of her left foot was a triangular iron padlock. Archaeologists also recovered fragments of an elaborate textile near her skull.
Microscopic analysis showed the material was silk decorated with metal threads made from silver and gilded silver. Such expensive trimmings were generally associated with aristocrats, nobility, and wealthy townspeople. Researchers, therefore, conclude that the teenager likely came from a relatively high social class, making her apparent treatment after death particularly unusual.
Analysis of her skeleton offered few indications about how she died. Researchers estimated that she stood roughly 5 feet 5 inches tall and found no evidence of fatal trauma or skeletal disease that might explain her death. Without any surviving soft tissue, however, determining a definitive cause of death may be impossible.
DNA confirmed the remains belonged to a female and placed her mitochondrial lineage within haplogroup J1c2c1, a lineage found particularly among ancient and modern Scandinavian populations.
Isotope measurements suggest she probably spent her childhood around Pień. One possibility is that she belonged to a family with more distant Scandinavian ancestry, although the researchers caution that genetics and isotopes cannot establish geographic origin with certainty.
More intriguing is evidence that the precautions surrounding her body were not all taken at the same time.
The padlock appears to have been attached when she was originally buried. The sickle may have come later.
Disturbed soil around the vampire grave suggests somebody subsequently reopened it. Because the skeleton remained articulated, researchers believe that, if it were reopened, it probably happened before the body had completely decomposed. At that point, someone may have placed or driven the sickle across her neck as an additional safeguard.
That raises a disturbing possibility that the community already regarded the young woman as potentially dangerous when she died. Yet, for unknown reasons, they became even more frightened of her after her burial.
Historical traditions provide some context. In parts of Poland, a sickle placed across the throat was believed to prevent a strzyga from returning. Birch, one possible wood identified in the sickle’s deteriorated handle, was itself associated with protection against demons and witchcraft.
There may have even been yet another precaution. Extensive green discoloration inside the skull suggests that an object containing copper could have been placed in her mouth. Chemical analysis could not determine what it was, although researchers say it was unlikely to be a coin. Objects inserted into the mouths of suspected revenants are known from other “anti-vampiric” burials.
None of this means the woman was literally considered a “vampire” in the modern Dracula sense. Instead, the evidence points toward a wider fear that certain dead people could return or somehow cause harm.
Why this particular teenager inspired such fear is still a mystery. Researchers suggest her ancestry, young age, an unusual or socially troubling death, disease, or behavior during life could all have contributed.
In periods of epidemic, famine, and other disasters, communities sometimes blamed supposedly dangerous dead people for otherwise inexplicable misfortune. Researchers stress that these explanations remain hypotheses, not proof of what her contemporaries believed.
For now, the only thing that seems certain is that the local community feared this young woman enough to secure her body not only once, but returned to her grave to secure it again.
“Grave 75, as well as other non-normative graves in the cemetery in Pien, demonstrate practices of a protective/anti-demonic nature,” researchers write. “[They] vividly illustrate superstitions, including the tendency to blame the deceased for misfortunes and the fear of the unknown in the 17th-century Polish-Lithuanian Commonwealth.”
The recent study, “A unique, non-normative burial of a young adult female from a 17th-century cemetery in Pień, north-central Poland. A multidisciplinary approach,” appeared in the Journal of Archaeological Science: Reports.
Tim McMillan is a retired law enforcement executive, investigative reporter and co-founder of The Debrief. His writing typically focuses on defense, national security, the Intelligence Community and topics related to psychology. You can follow Tim on Twitter: @LtTimMcMillan. Tim can be reached by email: tim@thedebrief.org or through encrypted email: LtTimMcMillan@protonmail.com
Diseases that cause nerve cells in the brain to die over time are known as neurodegenerative diseases. These cells, known as neurons, are vulnerable to DNA damage because they are highly active cells that require large amounts of energy. Neural DNA damage is a normal part of aging as changes to the DNA sequence, called mutations, build up over time.
Previous scientists have shown that neurons from people with the neurodegenerative diseases Alzheimer’s disease (AD), frontotemporal dementia (FTD), and amyotrophic lateral sclerosis (ALS) accumulate unusually high numbers of changes in the DNA sequence, called somatic mutations. However, researchers don’t know what causes the high number of mutations or whether the same process causes them in all 3 diseases.
To answer these questions, researchers at Boston Children’s Hospital and Harvard Medical School analyzed brain tissue from people who died with and without AD, FTD, or ALS. They compared the processes that cause DNA mutations in the 3 diseases by first accessing the DNA inside individual neurons from healthy and diseased postmortem brain tissue.
To do this, they broke apart the brain tissue and added a fluorescent marker that identified the center of each neuronal cell where DNA is housed, called its nucleus. They used a sorting machine to separate the nuclei from the rest of the cell material to access the neuron’s DNA. Using a DNA sequencing method called single-cell whole genome sequencing, the team then sequenced each neuron’s DNA to identify mutations.
They analyzed 159 neurons from people with AD, 61 neurons from people with FTD, 77 neurons from people with ALS, and 232 neurons from healthy individuals. This allowed the team to compare the number and types of DNA mutations between diseased and control (non-diseased) neurons. The researchers found that compared to the control neurons, which typically accumulate only 200 to 300 mutations over an 80-year lifespan, neurons from all 3 diseases contained an unusually high number of 2-base-pair deletions, often exceeding 1,000 mutations per cell.
When a biological process damages DNA, it leaves behind its own unique signature. By identifying these signatures, scientists can identify the biological process that likely caused the damage. Since these 2-base-pair deletions were so frequent in diseased neurons, the researchers wanted to know whether they were left behind by a biological process. The researchers used a machine learning algorithm to scan DNA sequences for recurring mutation patterns and identified a signature in neuronal DNA, which they named ID-4.
When the researchers compared the ID-4 signature with a database of previously characterized signatures, they found that it was associated with a DNA repair protein called TOP1. TOP1 temporarily cuts and rejoins DNA to relieve the tension that builds up during normal cellular activity. TOP1 typically detaches from the DNA after completing this process. However, if TOP1 fails to detach, it breaks one of the two DNA strands.
To test whether abnormal TOP1 activity was breaking the DNA, the researchers isolated DNA from control and diseased neurons. They visualized the DNA on a gel, where intact DNA forms bands while broken DNA spreads out into smears. The more fragmented the DNA is, the more intense the smear appears. Using a machine that quantified the intensity of smears, the researchers found that DNA from diseased neurons produced smears that were up to 3.2 times more intense than those from control neurons. They also found that neurons with more DNA fragmentation had more ID-4 signatures.
Based on these findings, the researchers concluded that abnormal TOP1 activity created frequent single-strand DNA breaks. They proposed that some of these breaks are repaired incorrectly, eventually leading to widespread DNA breaks in all 3 neurodegenerative diseases.
Overall, the researchers found that neurons from these 3 neurodegenerative diseases accumulated excessive DNA mutations despite differences in the disease symptoms and underlying causes. Their findings also provided evidence that abnormal TOP1 activity contributes to this mutation accumulation. Based on these findings, they stated that preventing TOP1 from becoming trapped on DNA, or improving the DNA repair process that removes trapped TOP1, could be a promising way to treat a wide range of neurodegenerative diseases.
The post Common DNA damage could cause neurodegenerative diseases appeared first on Sciworthy.
Bat DNA may hold clues to a long and healthy life, according to an international team of researchers.
These small creatures grace the night skies with extremely long lifespans and low cancer rates—traits that may ultimately benefit humanity if scientists can figure out how bats achieve them. Now, in a recent paper published in Nature, scientists from the University of Vermont and Penn State University led an international team investigating bats’ immune systems.
The paper’s crucial discovery was that bat DNA reveals the creatures encode genomic changes to handle exposure to environmental pathogens.
“Pathogen adaptation, longevity, and cancer resistance—they are fundamentally linked,” explained co-lead author Elise Lauterbur, an assistant professor of evolutionary biology at the University of Vermont. “Many of the genes that have adapted to viruses in bats are genes that are also involved in longevity and cancer resistance.”
Bats make an ideal study subject as they are only second to rodents in diversity, allowing scientists to study a wide variety of features in a single order.
“If you look at two bats, the same size, one lives 3 years the other lives 30 years and they are very closely related, like humans and Neanderthals, you can essentially find a very small number of genetic changes that leads to a very big change in their lifespan,” said co-lead author Juan Manuel “Manny” Vazquez, an assistant professor at Penn State University. “And that is kind of the Holy Grail for evolutionary medicine.”
The work focused on Myotis, one of the largest bat genera, whose members are found across much of the globe outside Antarctica. Eight Myotis species came under the microscope, with the team experimenting on cultured cells and analyzing their genomes. Among the species sampled were little brown bats (Myotis lucifugus), known both for their long lifespans, even among bats, and their susceptibility to the deadly white-nose syndrome, a fungal disease.
Even the researchers’ sample-collection methods were novel. They developed a technique akin to ear-piercing to collect small tissue samples from bat wings, which were then used to establish cell cultures. The team says this both spared the animals’ lives and produced more scientifically useful samples.
In their detailed examination, the researchers identified evidence of past events in which Myotis bats encountered pathogens and how adaptations to those viruses were selected for during their evolution.
Their work identified specific genomic changes, including the duplication or deletion of genes, associated with adaptation to environmental pathogens. This illuminated important differences in bats’ responses to DNA and RNA viruses compared with humans and other primates, potentially contributing to bats’ long, healthy lifespans.
Comparatively, human evolution shows stronger selection involving proteins that interact with RNA viruses like influenza, while bats show stronger selection involving proteins that interact with DNA viruses such as herpesviruses. These differences may help explain the distinct ways bats and primates have adapted to viral threats.
The team also identified genetic mechanisms that could help explain bats’ resistance to cancer and other age-related diseases. In some cases, duplicated genes can diversify their functions, allowing different copies to perform distinct roles. According to the researchers, this may provide immune advantages that help bats combat multiple viruses while also contributing to pathways associated with longevity.
Another important finding was that while most mammals contain one copy of the immune-related gene PRKN, some bat species contain two or even three copies, suggesting that additional copies may offer evolutionary advantages. The team says this could provide important insights for future cancer research, given bats’ unusual ability to repair or eliminate damaged cells.
The research doesn’t point to immediate treatments for humans, but it does provide starting points for reconsidering human illness in the context of bat immunology and evolution.
“Everything is connected,” Vazquez concluded. “Everything uses the same shared set of biology. … We don’t have to treat all of these different problems as silos. We can now start focusing on systems like bats to understand how we can solve multiple human age-related diseases.”
The paper, “Insights into Longevity and Virus-Driven Adaptation from Myotis Bat Genomes,” appeared in Nature on August 26, 2026.
Ryan Whalen covers science and technology for The Debrief. He holds an MA in History and a Master of Library and Information Science with a certificate in Data Science. He can be contacted at ryan@thedebrief.org, and follow him on Twitter @mdntwvlf.
A thousand years ago, feasts in what’s now northern Georgia state included cacao from Central America.
Potsherds discarded after an 11th-century feast at Etowah—an Indigenous city just north of what’s now Atlanta—contained traces of cacao, a raw ingredient of chocolate. The chemical residue and ancient DNA reveal that not only did the Mississippian people who built the city have excellent taste, they also had trade connections that reached at least 3,000 kilometers to Central America. And in a sense, chocolate may have helped build the Mississippian mounds.
University of South Carolina archaeologist Adam King and his colleagues found fragments of ancient DNA from Theobroma cacao in the inner surfaces of potsherds from long-ago feasts at Etowah. Fruit from the cacao tree contains beans that, when dried and roasted, produce chocolate in all its glorious forms. Cacao only grows in the tropics, which means the nearest actual cacao trees would have been at least a 3,000-kilometer trek away from the woodlands of the eastern US. And that means the Mississippian people who lived in Etowah must have had continent-spanning trade connections.
© Georgia Department of Natural Resources
New research involving tiny aquatic animals known as rotifers is providing scientists with a unique look at how information about maternal age may be passed from one generation to its offspring.
The findings offer insights into the ways a mother’s age can influence factors that range from health and lifespan to the behavior and even reproductive success of her offspring. This phenomenon, known as maternal age effects, has been documented throughout the animal kingdom—observed in everything from invertebrates to large land mammals like elephants, and even humans.
While advanced maternal age has often been associated with negative effects in offspring in past studies, questions remain about exactly how those effects are transmitted.
“Nearly all forms of life show some level of maternal age effect, and most are negative effects caused by advanced maternal age,” said Kristin Gribble, an associate scientist at the Marine Biological Laboratory’s Bay Paul Center, in a statement.
For their research, Gribble and her colleagues have focused on Brachionus manjavacas rotifers, a variety of microscopic aquatic creatures whose rapid reproduction abilities allow scientists a unique opportunity to study biological changes that occur across multiple generations.
Now, Gribble and her team’s findings point to something novel: that rather than being influenced primarily by accumulated DNA mutations, or even cellular damage, some maternal age effects appear to be epigenetic.
The new findings resulted from work undertaken in Gribble’s laboratory by researcher Alyssa Liguori, which looked at two different genotypes within a single species of rotifer.
The premise was simple: if mutations or cellular damage were what was behind maternal age effects, the consequences would likely be shown to worsen progressively across generations.
However, what the team found instead was that such effects could be reversed, and in some cases, within a single generation. The fact that this can occur so rapidly seems to imply that the underlying mechanism at play involves changes in the way genes are expressed, as opposed to alterations in the actual genetic code, as suggested in the past.
Based on this, one possibility the team is now exploring is that what are called histone modifications—essentially chemical changes that impact proteins that are encased with DNA, which can influence whether particular genes become activated, or suppressed.
Additionally, the researchers are now looking at whether mitochondrial DNA (mDNA), known to generally be inherited from an offspring’s mother, could play a key role in helping transmit information about maternal age from one generation to the next.
Further, genetic differences may influence how much an offspring is affected. One intriguing aspect of the recent research that Gribble emphasizes involves how one rotifer strain seemed to produce offspring from older mothers, which actually exhibited longer lifespans. This may suggest that some genetic variants could help to protect against, or possibly even reverse, factors that are generally negatively associated with advanced maternal age.
Still, a few mysteries remain, such as what exactly causes maternal age effects to remain so widespread, especially if they often reduce an offspring’s evolutionary fitness.
Gribble has an idea: she suspects that natural selection may provide at least part of the answer, since reproduction in rotifers occurs relatively early in life. This could mean that evolutionary pressures that eliminate harmful effects that may arise from reproduction at advanced ages could be comparatively weak.
Ultimately, the team believes their research may help to illuminate a much broader question: how the experiences and biological state of one generation influence those that follow.
“It’s not just about what’s in your genome as an individual,” Gribble said, adding that this is mainly because “your health potentially depends on the health and environment of your mom and grandmother and great-grandmother.”
Fundamentally, if researchers can identify the mechanisms behind maternal age effects in rotifers, these unassuming aquatic creatures could help to significantly advance our understanding of the ways biological information is carried across generations, potentially offering new insights into human health and precision medicine.
The team’s findings were detailed in a new paper, “Transgenerational and Intergenerational Maternal Age Effects Exhibit Complex, Genotype-Specific Patterns of Inheritance,” which appeared in The American Naturalist.
Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. A longtime reporter on science, defense, and technology with a focus on space and astronomy, he can be reached at micah@thedebrief.org. Follow him on X @MicahHanks, and at micahhanks.com.
Neanderthals vanished roughly 42,000 years ago, but a piece of their biology appears to be quietly at work in some people today, according to a new study led by scientists from the Max Planck Institute for Evolutionary Anthropology.
The post Neanderthal Gene Still Shapes Muscle and Jaws in Some Living Humans appeared first on Sci.News: Breaking Science News.
Ancient DNA may give some slightly more muscles today.More than 150 years after Charles Darwin first wondered whether certain sticky-leaved Saxifraga plants might be secretly carnivorous, Kunming Institute of Botany researcher Tao Deng and colleagues say they have finally confirmed it.
The post Scientists Add Unlikely New Member to World’s Carnivorous Plants appeared first on Sci.News: Breaking Science News.
Around 70% of the animals were female,New research led by the University of California, Berkeley reveals that beyond Neanderthals and Denisovans, humans interbred with two mysterious ‘ghost’ lineages: one in Africa more than 50,000 years ago, another in Eurasia over 1.7 million years ago.
The post Scientists Find Traces of Two Unknown Archaic Hominins in Human DNA appeared first on Sci.News: Breaking Science News.
New research has revealed the complex biological history preserved in DNA traces on the Shroud of Turin. Fibers taken from the Shroud of Turin nearly five decades ago still contain a complex record of biological material accumulated over centuries. In research published in Scientific Reports, scientists applied advanced genomic sequencing (rigorous PCR-free next-generation metagenomic sequencing) [...]In recent years, advances in ancient DNA sequencing have redefined our understanding of human evolution, revealing that our species did not emerge in isolation but repeatedly interbred with close evolutionary relatives like Neanderthals and Denisovans.
Yet one of the field’s greatest mysteries has remained unanswered: What if some of our ancestors also encountered extinct human groups whose DNA has never been recovered from fossils? Now, a recent study published in Science suggests researchers may finally have found a way to detect those long-lost relatives.
Instead of relying on ancient bones or preserved genomes, researchers developed a powerful computational approach capable of identifying genetic traces of previously unknown archaic humans using only the genomes of living people.
Applying the technique to modern populations around the world, the researchers uncovered evidence that an unidentified “ghost” hominin contributed DNA to the ancestors of all living humans before the great migration out of Africa.
Researchers also found new evidence providing evidence for the existence of an even older “super-archaic” human lineage whose genetic legacy may survive today through Denisovan ancestry in Oceania.
“Admixture between modern humans and extinct hominins has shaped the genomes of present-day individuals, but reconstructing this history has been constrained by the scarcity of archaic samples and unadmixed outgroup populations,” researchers write. “We introduce TRACE, a reference- and outgroup-free approach that uses features of ancestral recombination graphs to identify archaic ancestry.”
Past research has sequenced only a handful of high-quality archaic human genomes, all from Eurasia. While those genomes have revealed that most people outside Africa carry roughly 1 to 2 percent Neanderthal DNA and that many Asian and Oceanian populations also inherited Denisovan ancestry, scientists have long suspected those known groups represented only part of humanity’s evolutionary history.
Previous genetic studies had hinted that modern humans, especially African populations, contained fragments of DNA from unidentified archaic relatives. However, because no fossil genomes exist for those populations, proving their existence has been extraordinarily difficult.
The new method, called TRACE, short for “TRacking Archaic Contributions via ARG Estimation,” takes a fundamentally different approach. Rather than comparing modern DNA against known Neanderthal or Denisovan genomes, it reconstructs ancestral recombination graphs. These enormous evolutionary family trees trace how pieces of DNA have been inherited over hundreds of thousands of years.
These ancestral graphs preserve signatures left behind when deeply divergent human lineages interbred. Such events create unusually long branches and distinctive genetic patterns that can persist in descendants for hundreds of thousands of years. By searching for those signatures, TRACE can identify archaic ancestry even when no reference genome exists.
To test the system, the researchers first ran extensive computer simulations modeling ancient human populations and known episodes of Neanderthal interbreeding. The method consistently revealed high accuracy while producing very low false-positive rates.
The team then applied TRACE to genomes from the 1000 Genomes Project, encompassing hundreds of individuals representing populations across Africa, Europe, Asia, and elsewhere.
The program successfully recovered well-established Neanderthal ancestry in Europeans and Asians, along with Denisovan ancestry concentrated primarily in Asian populations. More intriguing, however, was the discovery of an additional category of DNA that matched neither Neanderthals nor Denisovans.
TRACE identified between roughly 0.5 and 1.1 percent “ghost” ancestry across all modern populations examined. The genetic evidence suggests these segments originated from an unknown archaic human lineage that diverged from our ancestors roughly 830,000 years ago, before later contributing DNA to the ancestors of modern humans.
Perhaps most surprising was where that ancestry appeared.
Rather than being confined to African populations, as several earlier hypotheses proposed, the researchers found remarkably similar ghost ancestry in both Africans and non-Africans.
Most of the segments detected outside Africa were shared with African populations, suggesting the interbreeding event occurred before modern humans started dispersing across the globe roughly 50,000 to 70,000 years ago.
The findings point toward a previously unrecognized chapter of human evolution in which an unidentified human population mixed with the common ancestors of everyone alive today.
The researchers also explored where these ancient genetic fragments survive in the modern genome.
They found ghost ancestry spread across more than 70 percent of the accessible human genome, although it was far from evenly distributed. Some regions contained unusually high concentrations of ghost DNA, including genes involved in immune function and metabolism.
Even more unexpectedly, ghost ancestry persisted inside genomic regions previously believed to be largely devoid of archaic DNA.
These regions, known as “Neanderthal and Denisovan ancestry deserts,” have often been interpreted as places where natural selection eliminated archaic genetic variants because uniquely modern human versions proved advantageous.
The presence of ghost ancestry inside many of those same regions suggests the story may be more complicated. Rather than rejecting all archaic DNA equally, natural selection may have acted differently depending on which ancient human lineage contributed the genes.
The study also ventured even farther back in evolutionary time.
Focusing on genomes from Papua New Guinea, Vanuatu, and the Santa Cruz Islands, the researchers searched for evidence of “super-archaic” ancestry—genetic contributions from a lineage that diverged long before Neanderthals, Denisovans, and modern humans separated.
Previous studies had suggested Denisovans themselves may have inherited DNA from such an ancient population. TRACE now provides additional support for that hypothesis.
The team identified deeply divergent genetic segments embedded explicitly within Denisovan-derived DNA in Oceanian populations. Based on their analyses, those ancient lineages may have split from the ancestors of modern humans approximately 1.77 million years ago.
While the researchers stress this represents a conservative estimate of surviving super-archaic ancestry, the findings strengthen the idea that modern humans indirectly inherited DNA from a much older human lineage through Denisovan interbreeding.
The identity of both the ghost lineage and the super-archaic population remains unknown.
The ghost population may represent Middle Pleistocene human groups or African populations of Homo heidelbergensis that encountered the ancestors of modern humans before the Out-of-Africa migration. For the older super-archaic lineage, the researchers note that Homo erectus remains one plausible candidate given its estimated divergence time and broad geographic distribution.
Although the new method cannot yet identify specific fossil species, it provides researchers with an entirely new tool for investigating chapters of human evolution that may never yield recoverable ancient DNA.
Because DNA older than roughly one million years is extraordinarily unlikely to survive outside permanently frozen environments, computational approaches like TRACE are becoming increasingly important for reconstructing humanity’s deepest evolutionary history.
“We find evidence for at least one ghost introgression predating the OOA expansion that contributed ancestry to all present-day populations,” researchers write. “These results point to multiple layers of introgression—both direct and mediated through other archaic groups—shaping modern human genomes.”
The study, “Recovering signatures of archaic hominin introgression using ancestral recombination graphs,” was published in the journal Science.
Tim McMillan is a retired law enforcement executive, investigative reporter and co-founder of The Debrief. His writing typically focuses on defense, national security, the Intelligence Community and topics related to psychology. You can follow Tim on Twitter: @LtTimMcMillan. Tim can be reached by email: tim@thedebrief.org or through encrypted email: LtTimMcMillan@protonmail.com
An international team of researchers who extracted ancient mammoth DNA from a sample of 500 bones reports that Ice Age humans selectively targeted female woolly mammoths.
The results of the team’s work show a contrast in sex ratio and mammoth remains, and found that the connection to large bones associated with ancient human activity was dominated by females.
“Whether these massive mammoth bone accumulations were formed naturally or by human hunting has been debated for decades”, says David Díez del Molino, Researcher at the Centre for Palaeogenetics and co-senior author of the study, in a statement. “By comparing the genetic sex ratios of hundreds of mammoths from natural settings with those found in these archaeological contexts, we can now infer that human activity was the primary driver behind these bone accumulations.”
The team took samples from a total of 521 woolly mammoths, including 448 individuals whose DNA was sequenced for the first time. The study, the team says, became the largest genetic analysis of mammoths ever conducted.
Archaeologists have been wondering for years if the large bone piles they found were created naturally or organized by humans. The new research pointed to a clear answer: these discoveries can be attributed directly to human hunting and organization.
The researchers determined the sex of each mammoth based on genetics and found that remains from natural settings were more likely to be male, with around 66 percent being males and 34 percent females. Scientists believe these reveal a direct connection to the behavior of mammoths, much like modern elephants, where adult males were more likely to be trapped in sinkholes or other related natural disasters, which would increase the chances of their bones being preserved, compared to females.
However, the sites connected to human organization and consumption told a different story. Around 70 percent of the mammoths found were female, suggesting that during the Ice Age, strategic hunting was being undertaken. The question remains why hunters preferred females over males, which also seems unusual since killing more female mammoths would decrease the population, and therefore decrease the overall food supply of Ice Age hunters.
“While it is tempting to assume that hunters would have targeted females because they were smaller than adult males, the reality may have been more complex. If mammoths behaved like modern elephants, females living in matriarchal herds may have had group defences that would have made encounters with herds equally or even more risky,” says Hannah M. Moots, Postdoctoral Researcher at the Centre for Palaeogenetics and lead author of the study.
Although females were generally smaller than fully grown bulls, researchers caution against assuming they were easier prey.
“Another possibility is that female-led herds moved across the landscape in more predictable ways than solitary males, meaning Upper Palaeolithic hunter-gatherers may simply have encountered them more frequently, whether for hunting or scavenging”, Moots adds. The researchers also suggest that female herds could have followed migration routes, therefore making their movements more predictable for Upper Paleolithic hunter-gatherers.
The study examined 11 major archaeological sites dating from 30,000 to 20,000 years ago, a time when mammoths were essential to human survival. Hunters during this period used nearly every part of the animal for food, clothing, shelter, tools, and even art.
By analyzing DNA from 100 mammoths found at archaeological sites and 421 from natural deposits, researchers assembled the largest dataset of its kind, revealing new insights into mammoth behavior and Ice Age hunting practices.
The analysis also uncovered the first known case of X0/XX mosaicism, a genetic condition similar to Turner syndrome in modern humans, in an extinct species. The affected mammoth, from Wrangel Island, provides a rare glimpse into the biology of these ancient giants.
The recent study, “Palaeogenomic sex inference of mammoth remains sheds light on the anthropogenic nature of bone accumulations,” appeared in the journal Current Biology.
Chrissy Newton is a PR professional and the founder of VOCAB Communications. She currently appears on The Discovery Channel and Max and hosts the Rebelliously Curious podcast, which can be found on YouTube and on all audio podcast streaming platforms. Follow her on X: @ChrissyNewton, Instagram: @BeingChrissyNewton, and chrissynewton.com. To contact Chrissy with a story, please email chrissy @ thedebrief.org.
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