A multispecies map reveals the secret animal campus hiding in plain sight.A new study reveals that oak trees can keep photosynthesizing for months after growth ends, challenging assumptions about how effectively forests convert absorbed carbon into long-term storage. A tree can look busy long after it has stopped building itself. Its leaves may still be absorbing sunlight and pulling carbon dioxide from the air, but deep [...]Researchers have captured the first atomic-level views of human SMUG1, a key enzyme involved in repairing damaged DNA. Every cell in your body is constantly battling damage to its DNA. Now, scientists have captured the first atomic level images of a key human repair enzyme in action, revealing how cells identify and remove some of [...]A surprising backup pathway allows cells to make a crucial amino acid when their primary machinery fails. For decades, biologists believed cells had only one way to access a molecule they cannot live without. New research suggests they were wrong. Scientists at Montana State University have uncovered a previously unknown cellular survival pathway that allows [...]A copper-based drug helped the brain flush out Alzheimer’s toxins, cutting plaque buildup and improving memory in a promising new study. Scientists at Monash University have identified a promising new approach to tackling Alzheimer’s disease. In laboratory studies, a copper-delivering drug significantly lowered levels of toxic proteins linked to the disease while also improving long-term [...]
New analysis of ancient frozen Greenland rubbish heaps, called middens, has revealed new insights into several ancient societies that have passed through the country over the last five millennia. The findings include insights into ancient diseases and animals that the inhabitants kept but didn’t eat.
Although the team noted the potential risk that climate change could release dangerous ancient microbes into the modern environment, their analysis found little evidence that the pathogens they identified could pose a threat beyond the immediate area around the middens.
Archaeologists have often excavated items discarded by ancient societies from trash heaps to learn more about the people who lived there. Although such excavations often unearth things like animal bones and mollusk shells, offering insights into diet and hunting habits, these ancient rubbish heaps can also contain human artifacts, such as discarded blades and other tools.
In a country like Greenland, where different peoples have settled the region since 2,500 BCE, the ancient middens may also contain microbes that could offer researchers an entirely different type of historical data. For example, microbial data from middens could reveal which diseases ancient populations had to survive. The team notes that microbes could also help determine what ancient societies kept “but perhaps didn’t eat.”
Still, studies of ancient midden microbes are limited, leaving a gap in historical knowledge. The authors of the new paper also highlight that rapidly increasing Arctic warming could release infectious diseases to which humans have lost immunity over the ensuing generations.
To bridge the information gap, Dr Frank Møller Aarestrup, a professor at the National Food Institute of Denmark Technical University and corresponding author of the article detailing the team’s research, examined samples collected during 2020 and 2021 expeditions in West and South Greenland. During those expeditions, scientists collected samples from middens locked in time by permafrost, dating back as far as 4,500 years.
Among the middens sampled were the ancient Norse sites of Kapisilit and Narsarsuaq, where researchers collected soil samples from what the new paper’s authors termed “historic winter enclosures.” The site also contained evidence that it was a summer grazing ground for livestock.
After selecting several soil samples, Dr. Aarestrup’s team sequenced the DNA of ancient microbes found in the midden samples. Next, they compared the data, including entire bacterial communities, to 143 soil samples previously collected from areas of permafrost far away from any known historical human settlements.
According to the team’s statement, the sequencing revealed a total of 1,207 species and differing ranges of bacterial species per midden. In denser areas, the team identified as many as 202 species, whereas less microbe-dense middens had as few as nine.
The team’s analysis also found several species that had not been previously identified. This resulted in the team labeling the unidentified microbes using what they termed “broad taxonomic categories” above the genus and species level, such as family and order.
When comparing the microbial communities in the ancient middens with those from samples collected away from human settlements, the team found a significantly richer community of ancient bacteria preserved in the middens. The team notes that this discrepancy confirms that the middens “preserved the biological legacy of human activity.”
The most soil-like bacterial communities were identified within the oldest Paleo-Inuit middens. The researchers said the finding suggests that the microbial “imprint” left behind by humans and animals diminishes over time.
Bacterial communities were also associated with the types of waste discarded in each ancient midden. For example, although most middens contained bacteria associated with human and animal hosts, middens from colonial-era Nuuk contained decomposing seal skins. The middens from colonial-era sites were also rich in the bacterium Clostridium perfringens, which the team notes is “a major cause of food poisoning.”
Although the team identified strains of bacteria that can cause botulism or other life-threatening conditions, such as toxic shock syndrome, sepsis, and gangrene, they also found a diversity of antimicrobial-resistance genes in the genomes of bacteria collected from the same middens.
According to the study authors, finding the two sets of genes in ancient and modern soil layers “signaled that microbes resistant to antimicrobials can linger in permafrost for centuries.”
Fortunately, the team’s analysis found that most of the identified microbes, including potentially dangerous pathogens, don’t spread far from middens, even those undergoing defrosting. As a result, the team said that these ancient microbes “pose little risk to public health,” at least for the time being.
“Here we show that the risk of release of ancient pathogens from ancient middens in Greenland is currently low,” Dr. Aarestrup explained.
Instead, the researcher noted that Arctic middens appear to function like “long-term natural experiments,” in which both human- and animal-associated bacteria, including “opportunistic” species carrying resistance genes, remain detectable centuries later as a broader “legacy of human activity.”
The study “Microbial composition of archaeological middens: Tracing Human Footprints Through Centuries in Greenland’s Ancient Settlements” was published in Frontiers in Microbiology.
Christopher Plain is a Science Fiction and Fantasy novelist and Head Science Writer at The Debrief. Follow and connect with him on X, learn about his books at plainfiction.com, or email him directly at christopher@thedebrief.org.
The floating device tests water, then disinfects it without batteries or chemicals.A self-regulating artificial photosynthesis system makes solar fuel without batteries, offering a simpler and potentially cheaper path to clean energy storage. Researchers at Osaka Metropolitan University have created a new artificial photosynthesis system that can produce solar fuel more consistently while eliminating the need for battery-based control systems. The advance comes from incorporating a self-regulating [...]Stonehenge’s giant Altar Stone likely traveled about 700 kilometers from Scotland through a carefully planned human effort. New research from Curtin University is shedding new light on one of Stonehenge’s biggest mysteries: how a massive stone weighing around six tons made its way across Britain thousands of years ago. The focus of the study is [...]The hunt for Planet Nine continues as new discoveries make the Solar System’s biggest mystery even harder to solve. Is there a massive undiscovered planet on the outer reaches of the Solar System? The idea has been around since before the discovery of Pluto in the 1930s. Labeled as planet X, prominent astronomers had put [...]Scientists studying the remarkable regenerative abilities of planarian flatworms have uncovered a previously unknown type of immune cell with an unusually destructive defense strategy. What if an immune cell could wipe out nearby threats by detonating itself? That is exactly what Stanford researchers have discovered in one of nature’s most unlikely creatures: the planarian flatworm. [...]A new passive technology could help future wireless networks reach places where signals struggle today. Dead zones are one of the most persistent problems in wireless communications. Whether it’s a basement office, a warehouse aisle, a tunnel, or a crowded indoor venue, signals often struggle to reach every corner. The challenge is expected to grow [...]A new detector-based method clarifies how gravitational waves should be measured in an evolving universe. Imagine trying to measure a ripple on the surface of a pond while the pond itself is slowly changing shape. That is the challenge scientists face when they study gravitational waves not as isolated signals from colliding black holes, but [...]Researchers have created a model that follows food beyond traditional calorie calculations, incorporating the role of gut microbes in digestion. Food labels make calorie counts look straightforward. The number listed per serving is calculated from the food’s fat, carbohydrate, and protein content. In reality, the digestive process is much more complex. As food moves through [...]A new study reveals that aging changes the body’s walking strategy, prioritizing balance and safety over efficiency. Walking may seem automatic, but every step requires a complex balance between stability, muscle coordination, and forward propulsion. As people age, that balance begins to shift. New research from Australia suggests the body gradually adopts a more cautious [...]Scientists have finally captured a hidden state of matter, revealing a long-predicted phase with intriguing quantum potential. Researchers from Brown University and the University of Michigan College of Engineering have succeeded in stabilizing a previously elusive state of matter that had existed only in theoretical models. Using carefully engineered nanoparticles as building blocks, the team [...]
Login