New Research Questions Decades of Low-Fat Dairy Advice

By B. Zou, U. of Toronto, August 3, 2026

https://scitechdaily.com/new-research-questions-decades-of-low-fat-dairy-advice/

Full-fat dairy may have a more nuanced effect on the body than nutrition labels imply. Researchers found no meaningful adverse changes after regular consumption and observed several unexpected nutritional and cardiovascular signals. 

Credit: Shutterstock

Researchers found that people can consume three daily servings of full-fat dairy without adversely affecting body weight, body composition, energy metabolism, or blood lipid levels.

For years, people scanning the dairy aisle have often been steered toward skim milk and reduced-fat products, largely because full-fat dairy contains saturated fat. Yet the health effects of dairy may depend on more than the amount of fat listed on the label.

Research led by University of Toronto scientist Harvey Anderson found that adults could consume three servings of full-fat dairy each day without harmful changes in body weight, body composition, energy metabolism or blood lipid levels. The results were published in the Journal of Nutrition.

Testing full-fat dairy directly

To examine the effects under controlled conditions, Anderson and his colleagues recruited 74 adults with overweight or obesity and randomly placed them into one of three dietary groups. One group followed a low-dairy, calorie-restriction diet. A second consumed three daily servings of dairy while keeping calorie intake energy-neutral, meaning participants ate roughly the amount of energy their bodies used. A third group also consumed three daily servings but did not face calorie limits. All participants were encouraged to follow Canada’s food guide.

Harvey Anderson.

 Credit: Harvey Anderson


 
This design allowed the researchers to separate the effects of dairy from those of calorie restriction. After 12 weeks, participants consuming three servings of dairy showed no meaningful differences in weight gain, body composition or cholesterol compared with those eating the low-dairy diet.

The higher dairy groups also recorded lower blood pressure and consumed more calcium, protein and vitamin D, nutrients that support functions such as bone maintenance, muscle health and immune activity.

“Those who had three servings of dairy didn’t have adverse levels of blood cholesterol or lipids or evidence of insulin resistance,” says Anderson, a professor of nutritional sciences in U of T’s Temerty Faculty of Medicine.

Insulin resistance occurs when the body’s cells stop responding properly to insulin, the hormone that helps move sugar from the bloodstream into cells for energy. Over time, that reduced response can increase the risk of type 2 diabetes.

Guidelines face conflicting evidence

Nutrition guidelines in Canada and many other countries have long favored fat-free or low-fat dairy. The reasoning is that reducing saturated fat may help prevent high cholesterol and lower cardiovascular disease risk.

Human research, however, has not consistently shown that eating full-fat dairy leads to worse health outcomes, Anderson says. Some investigations have even identified possible protective effects. Those include recent work led by Kozeta Miliku, an assistant professor at Temerty Medicine.

The apparent contradiction may come from viewing saturated fat in isolation rather than considering the food that contains it. Anderson and other researchers point to the dairy matrix hypothesis, which proposes that a food’s physical structure changes how its nutrients are broken down, absorbed and used.

In practical terms, dairy is not simply a collection of separate nutrients. Its proteins, fats, minerals and other components are packaged together, and that arrangement may influence how quickly they reach the body and what effects they produce.

“With dairy products, it’s got two proteins – casein and whey – that are bound together with fat and with nutrients mixed in,” Anderson says, adding that it’s this unique and complex physical structure that is responsible for the slow and steady delivery of nutrients from dairy products, and that expands their health impacts to more than just the sum of the isolated nutrients.

Whole foods reshape nutrition advice

The findings may be particularly useful for older adults, Anderson notes. As people age, their overall energy needs often decline even though they still require adequate protein, calcium, vitamin D and other nutrients.

That creates a practical challenge. Older adults may need to obtain more nutrition from fewer calories. Dairy products offer a familiar source of concentrated energy and nutrients, Anderson says, and the study found no evidence that including them increased the risk of diabetes or other chronic diseases.

The results also support a broader shift in nutrition research. Instead of judging foods mainly by a single component, such as saturated fat, researchers and policymakers may need to consider how nutrients behave when consumed together in a whole food.

Faced with constantly changing trends in food and nutrition and sometimes conflicting messaging around diet, Anderson’s advice is straightforward: “Keep it simple, eat a variety of foods and not too much of anything.”

The Life of Earth

https://chuckincardinal.blogspot.com/

Ecosystems of Rock-Eating Fungus And Tardigrades Found Thriving Deep Within a Gas Shale

03 August 2026, By J. Cockerill

https://www.sciencealert.com/scientists-discover-entire-ecosystem-hundreds-of-feet-below-earths-surface-at-depths-thought-inhospitable-to-life

Researchers have cultured hundreds of fungal strains from water samples pumped out of gas wells.

  (Quinn Moon, University of Michigan)



Just about every corner of Earth we look at seems to hold signs of life.

Now, scientists have discovered evidence of a whole community of complex organisms – fungi, worms, and even tardigrades – that call the Antrim Shale home.

That's pretty surprising, given the Antrim Shale is an ancient deposit of organic-rich mud some 350 million years old that now serves as one of the United States' largest gas fields.

But when scientists got to look for DNA in the water being pumped up from wells dug 247 to 556 meters (810 to 1,824 feet) deep into the ground, they found an astonishing diversity of life.

Organic-rich rocks and water deep within the Antrim Shale teem with life. They are packed with fungi and other tiny organisms.

 (John Megahan/University of Michigan)

"Energy companies dig these wells and pump massive amounts of water out and strip the methane from the water," ecologist Quinn Moon, lead author of the study, told ScienceAlert.

Moon, who is based at the University of Michigan, worked with a team of mycologists and earth scientists to get a picture of the organisms that might be living in this seemingly inhospitable environment.

"We filtered huge quantities of water and extracted DNA from those filters. We also put the water onto nutrient media to grow the actual fungi," Moon explained.

"Many deep environments, including the Antrim Shale, have extensively been shown to contain bacteria and archaea."

That had him wondering what else might be living down there.

An astonishingly complex and lively ecosystem emerged.

"Our findings challenge the common assumption that fungal regulation of organic matter decomposition is constrained to surface ecosystems," Moon and his colleagues write in their scientific paper, which was recently published in The ISME Journal.

Within these water samples, they identified 689 likely species of fungi from snippets of their genetic material, and managed to grow 205 strains in the lab for better identification.

Thirteen of those fungal strains are thought to be entirely new to science.

One of the dominant classes of fungi was Agaricomycetes, which are probably the best-known kind of fungi because they're the ones that produce mushrooms, though it's unclear whether they'd actually be capable of producing the parasol-like caps so far below ground.

The researchers isolated and grew more than 200 kinds of fungi from the deep subsurface to better understand how fungi survive in extreme environments, how underground ecosystems function, and what happens to carbon stored in Earth's crust. (Ronan Montgomery-Taylor/University of Michigan)



But the metabolisms of this kind of fungi – along with the other dominant class Moon and team discovered, Dothideomycetes – may explain their success in the shale.

On the surface, both of these kinds of fungi are known to break down lignin and cellulose for energy. These are substances that other organisms struggle to digest.

"These fungi make a living by eating some of the carbon forms most difficult to break down," Moon told ScienceAlert.
 
"I think the explanation is, and this aligns with other data from the surface, that these wood decay mushrooms have the most extensive arsenal of enzymes that they use down there to break down lignin and cellulose in the shale (or compounds similar to lignin and cellulose)."

Research is ongoing to screen the fungi's ability to break down coal, shale, oil, plastic and other difficult substrates. (Quinn Moon, University of Michigan)



Fungi made up about one-sixth of the biomass in the water samples, with a relative abundance comparable to what is found in the open ocean and Antarctic soils: about 250 fungal cells in each drop of water.

Alongside these fungi, the scientists found genetic traces of rotifers (microscopic 'wheel animals' you might've seen in pond water), segmented worms, tardigrades, and roundworms.

They even found evidence of intracellular parasites such as Ichthyosporea, which infects animals, and Rozellomycota, which parasitize other fungi.

It wasn't possible for the researchers to get a clear sense of the oxygen levels available to these creatures, so it's still unclear exactly how they're surviving down there.

As they note in their paper, the process of pumping water to the surface can introduce dissolved oxygen to samples that may not actually be available all the way down.

Previous studies have found the Antrim Shale hosts many species of archaea that produce methane, which is a sign this subterranean environment is pretty low on oxygen.

Others suggest that even without a supply of oxygen from the surface, some microbes may be capable of actually producing large amounts of oxygen without the help of light.

The researchers used a stain to count the number of fungi cells within each sample taken from Earth's subsurface.

 (Quinn Moon/University of Michigan)



But based on oxygen and hydrogen isotopes in the water, and the salinity gradient across sample sites, the team believes this underground community has been enjoying relatively stable geochemical conditions ever since the Late Pleistocene.

Much of the water hauled up in this study had not seen the light of day for 11,000 years, Moon said.

The microbes' ancestors were probably first introduced to these deep subsurface environments when Late Pleistocene ice caps melted, and the water seeped into the shale's pores and cracks.

So not only are these fungi living their lives at unfathomable depths; they have probably been isolated there for millennia, adapting to a set of evolutionary pressures entirely different from their aboveground counterparts.

And, as humans so often do, we started disturbing them before we even realized they exist.

"These may be biodiversity hotspots, but are also hotspots for anthropogenic destruction," Moon told ScienceAlert.

"These deposits have so many wells dug into them, many injected with biocides, without us ever considering if these habitats have new species and how we can preserve them."

The researchers also point out that fungi – so often overlooked – really need to be incorporated into models of carbon cycling and sequestration in the subsurface.

About 90 percent of Earth's organic carbon is stored in the deep subsurface, so it's a pretty significant part of the equation when it comes to balancing our climate.

If these fungi, bacteria, and other organisms are actively using these deep rocks, that carbon may not be quite so 'sequestered' as we imagine.

"If there are many organisms that can eat it, those gases can rapidly be released to the atmosphere," Moon said.

The Life of Earth

https://chuckincardinal.blogspot.com/

This Tiny Organ Plays a Far More Profound Role in Human Longevity Than We Realized, Study Finds

04 August 2026, By P. Dockrill

https://www.sciencealert.com/this-organ-plays-a-far-more-profound-role-in-human-longevity-than-we-realized-study-finds

(janulla/Getty Images)

A small organ located in the upper chest has been plagued by an identity crisis for decades now.

The thymus, which plays a crucial role in early life in helping to develop children's immune systems, is known to decay and shrink with age, leading to it often being considered a relatively useless or defunct organ in adults.

But research is showing this maligned "immune cell graveyard" doesn't actually lose its purpose when we grow up, as many had thought.

In fact, recent research published in Nature suggests the thymus could have a persistent and profound impact on health and longevity throughout people's lifetimes, helping the body counter disease risk, including cancer.

"We suspected the adult thymus might still matter, but we were surprised," oncologist Hugo Aerts from Harvard University, director of the Artificial Intelligence in Medicine (AIM) Program at Mass General Brigham, told ScienceAlert.

"We did not expect these differences to be so strongly and consistently associated with longevity, cancer incidence, cardiovascular disease, and cancer therapy response across multiple large, independent cohorts. That suggested the adult thymus is far more important than previously appreciated."

In their study, Aerts and his team analyzed health data from over 27,000 people, collected in two separate cohorts, the Framingham Heart Study (FHS) and the National Lung Screening Trial (NLST).

https://www.youtube.com/watch?v=W67LzQF6YqQ

In each study, people had taken part in computed tomography (CT) scans, which measured the size, shape, and composition of their thymus.

This data was fed into a deep learning system that was able to quantify the health of their thymus, based on these differing characteristics.

The AI could then generate a thymic health score – a kind of proxy for how functional the thymus was in adulthood – classifying each person as having either low, average, or high thymic health.

Follow-up data from each cohort showed that thymic health was linked with dramatically altered health outcomes in the years following the CT scans.

After adjusting for age, sex, smoking, and comorbidities, the researchers found that participants in the NLST with high thymic health had a roughly 50 percent lower relative risk of death by 12 years later, when compared with individuals with low thymic health from the study.

Similarly, people with high thymic health were about 36 percent less likely to develop lung cancer, and about 50 percent less likely to die from lung cancer compared to the low thymic health group.

Illustrations of three representative examples of individuals with high, average, or low thymic health. The thymus bed is outlined in orange.

 (Bernatz et al., Nature, 2026)



Cardiovascular disease also showed considerable relative risk reductions, with high thymic health corresponding to 63 percent lower risk of cardiovascular death in the NLST, and up to 92 percent lower risk in the FHS, compared to those with low thymic health.

The findings warrant replication in future research, and only show correlations in the data; they can't definitively prove that having a healthier thymus leads to these gains in health.

But the results still go a long way to suggesting that we need to update our understanding of how the thymus may be contributing to adult health and lifespan.

"These findings change how we think about the immune system in medicine," Aerts told ScienceAlert.

"Our work suggests that thymic health is a fundamental component of that immune fitness and that it can now be measured using routine medical imaging. This opens the possibility of identifying patients who are most likely to benefit from certain therapies, tailoring treatments to preserve immune health, and developing new strategies to maintain immune function as we age."

In a separate but related Nature study led by Aerts and published alongside the first paper in March, the researchers found that thymic health was also linked to immunotherapy responses across several types of cancer, including lung cancer, melanoma, breast cancer, and others.

One takeaway is that the thymus might not only be an unappreciated factor boosting people's health and longevity – it could also help us develop and target new kinds of treatments.

"The first turning point came when we discovered that patients with healthier thymuses responded much better to immunotherapy and survived longer," Aerts said.

"That finding was surprising because the thymus has long been considered largely irrelevant in adults. Initially, we wondered whether this was something unique to cancer treatment.

"But as we expanded the research into large population cohorts, we found that thymic health was also strongly associated with overall survival, cancer risk, cardiovascular disease, and other major health outcomes. At that point, it became clear that we weren't just discovering a new cancer biomarker, we were uncovering a much broader measure of adult immune health."

But what is it about the thymus that may have such a marked influence on people's health in adult life?

We don't know for sure, but the new findings echo a landmark study published in 2023, which discovered that people who had their thymus surgically removed faced an increased risk of death from any cause in the five years following their operation.

In contrast to the established view that the importance of the thymus diminishes with age, those findings supported "a role for the thymus contributing to new T-cell production in adulthood and to the maintenance of adult human health," the research team – led by Harvard University oncologist David Scadden – wrote in their paper.

The newer research arrives at a similar conclusion, suggesting that just because the thymus may shrink with age, that doesn't mean its gradual disappearance is a harmless vanishing act.

Aerts' team found that several lifestyle and health factors were linked to having poorer thymic health, including smoking, obesity, and chronic inflammation.

Putting it all together, it's suggestive of a two-way relationship.

A healthier thymus appears to help protect the body by producing better immune function through adulthood, but also inflammation, harmful habits, and disease can in turn hurt the organ, which may then proceed to weaken and shrink as people get older.

Those developments, once considered inevitable and normal, could instead be actionable – and longer, healthier lives may hang in the balance.

"I'm excited because this is more than the discovery of a new biomarker," Aerts said.

"It suggests that we've overlooked a major aspect of human biology for decades. If these findings continue to be confirmed, preserving and measuring immune health could become a new principle of medicine, much like we currently monitor heart or kidney function.

"The thymus may be one of the first organs that allows us to do that in a practical way."

The Life of Earth

https://chuckincardinal.blogspot.com/

'Natural Protection From Asthma And Allergies': Scientists Isolate Bacteria Behind The Immune System Farm Effect

02 August 2026, By J. Cockerill

https://www.sciencealert.com/natural-protection-from-asthma-and-allergies-scientists-isolate-bacteria-behind-the-immune-system-farm-effect

(Teerasak1988/iStock/Getty Images Plus)

For decades, scientists have theorized that kids actually need to get a bit dirty for their immune systems to develop fully.

It's known as the 'hygiene hypothesis'. And, as childhood rates of allergies, asthma, and hay fever rose drastically in industrialized Western nations, scientists noticed the same did not go for children raised on farms.

"Girls and boys who grow up on farms and are exposed to a wider variety of microbes have the problem far less often," says epidemiologist Markus Ege, of LMU University Hospital and the Institute of Asthma and Allergy Prevention at Helmholtz Munich in Germany.

That phenomenon is known as 'the farm effect'.

Now, Ege and his colleagues have found exactly which bacterial species mediate the farm effect in rural European children. This discovery goes some way towards verifying the hygiene hypothesis once and for all.

https://www.youtube.com/watch?v=n6jVWm7gsIU

Referring to the hygiene hypothesis, Ege says, "this kind of research can only show more or less convincing correlations."

"But with our new study, we can make a much stronger case," he continues, "because we can identify the individual links in the proposed causal chain: the bacteria, the relevant microbial metabolic products, and the human receptors."

Allergies, asthma, hay fever, and eczema: all of these conditions arise when the body's immune system unleashes an exaggerated immune response to harmless triggers.

If the hygiene hypothesis really has legs, scientists should be able to find specific microbes that, when humans are exposed to them, somehow give our immune systems the challenge they need to develop a more appropriate response, reducing the incidence of immune conditions.

In the new study, the researchers pointed the finger at nine suspect bacteria species.

"We identified a small number of bacteria, which we can now pinpoint down to the species level, such as Romboutsia timonensis and Glutamicibacter arilaitensis," explains bioinformatician Giulia Pagani, of Helmholtz Munich.

"These gram-positive bacteria together mediate two-thirds of the entire farm effect for asthma protection and half of the effect for hay fever and atopic eczema."

Cows could be your immune system's best friends. 

(Fly View Productions/E+/Getty Images)



The researchers discovered these species in dust samples collected from the mattresses of 1,018 rural South German schoolchildren, and the cow shed air at the farms of 47 of the kids.

The nine bacteria linked to the farm effect made up 6 percent of the relative abundance of microbes in mattress dust, but 25 percent in the cow shed samples.

Kids who were exposed to these microbes, and especially those who lived on farms, were much less likely to develop childhood asthma, in a classic example of the observed farm effect.

These microbes originate from the guts of cows, and then wind up in their poop, which may be how they become suspended in the air in cow sheds.

Farm kids spend time around cows, inhale the microbes, and, as their presence in mattress samples suggests, bring the microbes back into their homes where moderate exposure may continue.

That moderation is an important factor here, given the bacteria produce metabolites known to activate a receptor known as AhR, which triggers immune signaling and gene expression.

"High levels of AhR activation are detrimental, whereas moderate levels, as they may occur by inhalation of bacterial metabolites in cow sheds, are beneficial," the team writes.

When activated, AhR induces a strong anti-inflammatory response which may help prevent the development of asthma and allergies.

Scientists will need to conduct further experiments to determine the exact mechanisms by which these bacteria mediate the farm effect, since an observational study like this doesn't show that level of detail, and can't prove cause.

But the chain of events, from cow to bacteria to air to child's immune system, is finally coming into focus.

"Taken together, this analysis describes a strong and consistent association between specific environmental exposures and natural protection from asthma and allergies," the authors write.

"Broken down to a molecular level, these results may advance understanding of the mechanisms of asthma and allergy protection. Ultimately, this may foster the development of effective and well-tolerable prevention strategies for the most common chronic conditions in childhood."

The Life of Earth

https://chuckincardinal.blogspot.com/

Some Dolphins Use Tools, And It Does Something Unique to Their Genes

03 August 2026, By S. Vartan

https://www.sciencealert.com/some-dolphins-use-tools-and-it-does-something-unique-to-their-genes

A Shark Bay dolphin using a sponge as a foraging tool.

  (Stephanie King/University of Bristol)

A small population of dolphins in Shark Bay, Australia, do something very unique: They use a marine sponge to cover their snouts as they probe the seafloor for fish that are hidden just under a layer of sand.

The sponge not only protects their mouths from the abrasive sand, it also allows them to sweep over a larger area than their snout alone would, and they can forage in deeper waters too.

Humans have known about this ingenious technique for over 25 years, and it's just one example of dolphins using tools.

Dolphins in Shark Bay have also been spotted using a shell to scoop up and gulp down fish – a trick called shelling that, as researchers discovered in 2020, the animals learn from their friends.

On the other hand, sponging is a skill passed from mother to calf. It's a tricky task to learn because the sponge messes with the dolphins' echolocation abilities. Yet it seems useful enough for these dolphins to perpetuate over generations.

Now, researchers have discovered that these sponge-loving Shark Bay dolphins aren't just distinct in their behaviors.

https://www.youtube.com/watch?v=w12LU39Hmys

Dolphins that practice this learned sponging behavior also carry subtle differences in their epigenome, the collection of reversible chemical modifications that influence how genes are used without altering the DNA sequence itself.

In other words, this kind of cultural practice may leave a biological fingerprint.

"The potential interplay between culture and epigenetics has been little explored outside humans," the team, led by evolutionary biologist Michael Krützen of the University of Zurich in Switzerland, explains in their new paper.

"Understanding these interactions will not only provide novel insights for behavioral ecologists but might also shed light on human evolution, bridging the gap between cultural practices and their biological underpinnings."

Only a subset of Shark Bay's Indo-Pacific bottlenose dolphins (Tursiops aduncus) practice sponging, primarily females, and it's energetically costly, though it also seems to have specific benefits.

Spongers spend more time foraging, rest less, and often hunt alone. But they also eat different prey, have distinct social networks – and their resourcefulness might help them be more resilient in the wake of marine heatwaves, when typical food sources are scarce.

Despite sharing the same waters and often being closely related, some dolphins learn the technique while others never do.

That made the population an ideal natural experiment for asking whether a culturally transmitted behavior might be associated with epigenetic differences.

To investigate, researchers analyzed skin samples from 96 dolphins collected over more than two decades. Twenty-three were confirmed spongers, while 73 overlapping neighbors were non-spongers.

The team examined nearly 30,000 sites across the dolphins' genomes where DNA methylation – a common epigenetic modification – can occur.

DNA methylation acts like a dimmer control rather than an on-off switch. By attaching tiny chemical tags called methyl groups to DNA, cells can dial gene activity up or down without changing the genetic code itself.

Scientists have traditionally thought that epigenetic changes switch genes either "on" or "off", but research shows those changes can also 'dial down' gene expression in a graded way.

(Christine Daniloff, MIT; NIH)


These patterns are known to shift in response to age, diet, stress, and environmental conditions, making them plausible candidates for reflecting differences in lifestyle.

The researchers trained a machine-learning model to see whether methylation patterns alone could distinguish spongers from non-spongers. It could – but only moderately well.

No single methylation site stood out after correcting for the tens of thousands of statistical comparisons.

Instead, the predictive signal appeared to be spread across many small differences. The final model relied on methylation patterns at 21 DNA sites rather than one standout genetic marker.

That fits with what biologists increasingly see in complex behaviors: They're rarely controlled by a single gene or molecular pathway.

But this raises a chicken-and-egg question.

Cultural behaviors like sponging don't just change an animals' actions – they can reshape their diets, social lives, energy expenditure, and exposure to environmental challenges, as it has with these dolphins.

Those factors could, in theory, alter methylation patterns over an individual's lifetime. But research in roundworms suggests that epigenetic changes can also be inherited, transferred from one generation to the next.

So the researchers don't know whether learning to sponge changes methylation, whether pre-existing methylation differences somehow make dolphins more likely to adopt the behavior, or whether both are shaped by other factors linked to the sponging lifestyle.

Another study limitation here is ethical; the research team analyzed skin, the only tissue that can be collected safely from wild dolphins. But it may not fully reflect changes occurring in the brain or other organs involved in behavior.

But this is another great example of how researchers can better understand the biology of culture.

Evolutionary biologists have long understood that culture can eventually shape genetics over many generations – the spread of lactose tolerancein dairy-farming humans is one example.

This study, and others looking at epigenetic changes, suggest that there may be a faster way for bodies to communicate survival strategies (or just better nutrition) using the biological messaging of the epigenome.

The Life of Earth

https://chuckincardinal.blogspot.com/

1.4-Million-Year-Old Footprints Reveal a Giant Human Relative

By Max Planck Inst. for Evolutionary Anthropology, August 2, 2026

https://scitechdaily.com/1-4-million-year-old-footprints-reveal-a-giant-human-relative/

One of the large, 1.4-million-year-old footprints that the team excavated. A 6-inch (~15 cm) ruler is shown for scale.

 Credit: Kay Behrensmeyer

A 1.4-million-year-old trail of footprints reveals that a powerful human relative grew nearly as large as us and may have traveled in all-male groups.

Eight individuals walked across the wet ground beside an ancient Kenyan lake. Within a short time, sediment buried their footprints and preserved a scene that would remain hidden for roughly 1.4 million years.

The tracks offer something bones rarely can: evidence of several extinct human relatives moving through the same place at nearly the same moment. Researchers believe the footprints were left by a group of Paranthropus boisei, a powerful-jawed hominin that lived alongside early members of the human genus but ultimately disappeared without leaving descendants.

All eight individuals appear to have been adults, and most may have been males. Their apparent decision to travel together raises the possibility that Paranthropus boisei had a more complex social life than its fragmentary fossil record has revealed.

A Surprisingly Large Human Relative

The footprints also overturn a long-standing assumption about the species. Some were made by individuals approaching 1.8 meters (5 feet 11 inches) tall and 75 kilograms (165 pounds), dimensions comparable to those of many people today.

“The sizes of the footprints indicate human-like body sizes, up to 1.8 meters (5 feet 11 inches) tall and around 75 kilograms (165 pounds),” said lead author Kevin Hatala of Chatham University, who is also associated with the Department of Human Origins at the Max Planck Institute for Evolutionary Anthropology in Leipzig.

Kevin Hatala and colleagues discuss the ancient footprints excavated in northern Kenya in 2023.

 Credit: Kay Behrensmeyer



That size was unexpected because Paranthropus boisei has long been reconstructed largely from skulls rather than complete skeletons. Its most recognizable features include a broad face, enormous molars, and powerful chewing muscles, adaptations that once earned it the nickname “Nutcracker Man.”

Far less is known about the animal below the neck. Earlier estimates based on scarce limb bones suggested that Paranthropus boisei was substantially smaller than Homo erectus, another hominin living in East Africa at the time. Homo erectus had more human-like body proportions and may lie directly along the evolutionary path that eventually produced our species.

Footprints Reveal Two Hominin Species

The new tracks complicate that comparison. At least some Paranthropus boisei individuals may have rivaled Homo erectus in height and body mass, even though the two species had very different skulls, diets, and evolutionary histories.

Researchers assigned the footprints to Paranthropus boisei using analytical methods the team introduced in 2024. The approach compares details of foot shape and walking motion preserved in the tracks, allowing scientists to distinguish prints made by different hominin species.

Earlier work in the same region identified footprints from both Paranthropus boisei and Homo erectus on one ancient surface. That discovery provided direct evidence that the two species used the same lakeshore environment and may have encountered one another.

The newly studied tracks reveal a different kind of scene. Instead of two species crossing the same ground, they appear to record a group of Paranthropus boisei moving together.

Clues to a Complex Social Life

The absence of obvious juveniles or females is particularly intriguing. Although footprints cannot reveal the exact relationships among their makers, the apparent group of mostly adult males may point to social arrangements involving both competition and cooperation.

“The fact that eight, mostly adult male, Paranthropus boisei individuals seemingly traveled together as a group, without females or children, hints at a complex social structure in this species,” said co-author Neil Roach of Harvard University.

“They may have lived in large groups, where males competed for mates, but also tolerated each other at times for safety in a dangerous environment.”

Reconstructing an Extinct Hominin Group

Footprints record only a brief event, and researchers cannot determine whether the individuals regularly traveled together, had gathered temporarily, or were moving independently through the same area over a short period.

Even so, the scene expands Paranthropus boisei beyond the familiar image of a heavily built skull in a museum case. It presents the species as a living animal that walked upright, navigated a shared landscape, and may have formed organized groups.

The location of the tracks also matters. Scientists have now documented hundreds of hominin footprints at more than six sites around East Turkana, suggesting that lakeshores repeatedly attracted ancient human relatives for more than 100,000 years.

These environments would have offered water and food, but they may also have brought danger. Large predators and competing hominins could have gathered near the same limited resources, possibly making group travel advantageous.

“To me, it is amazing that we have the same kind of lake margin deposits in two areas of East Turkana that are 40 kilometers (25 miles) apart, at about the same age,” said co-author Kay Behrensmeyer of the Smithsonian Institution.

How Ancient Footprints Were Preserved

The footprints survived because a rare sequence of events protected them. Hominins first crossed soft, impressionable sediment near the water. New layers then covered the surface before wind, waves or other animals could destroy the tracks. Over immense spans of time, the sediment hardened and preserved their shapes.

Understanding that process could help researchers locate additional footprint surfaces and reconstruct why several hominin species returned so often to the lake.

“If we can understand what geological conditions allowed these tracks to be preserved, we should know more about why hominins continued to return to the lakeshore environment over more than 100,000 years,” Behrensmeyer said.

A Record of Prehistoric Daily Life

Each new surface captures only a few moments, but together they are beginning to form a record of movement, body size, habitat use, and social behavior that fossilized bones alone could never provide.

“Each site represents a snapshot of our past, and we are quickly building a photo album with several different windows to hominin anatomy, locomotion, behavior, and environments during the Early Pleistocene,” Hatala said.

That growing collection is transforming the ancient shores of Lake Turkana into something close to a prehistoric record of daily life. Instead of showing only who existed, the footprints reveal where extinct human relatives went, how they moved, and, occasionally, who walked beside them.

The birth of modern Man

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Why Dreaming Leaves the Brain Running Low on Energy

By Tohoku U., August 1, 2026

https://scitechdaily.com/why-dreaming-leaves-the-brain-running-low-on-energy/

A mouse study reveals that the dreaming brain may consume energy faster than it can replace it. This hidden metabolic imbalance could offer new clues about how REM sleep supports complex internal processing. 

Credit: Shutterstock

The dreaming brain surges with energy, yet its neurons may consume it faster than they can replenish it.

A new mouse study from Tohoku University has uncovered a surprising energy imbalance during rapid eye movement (REM) sleep. As the brain entered this dream-rich stage, blood volume increased across the cortex, and astrocytes accumulated more metabolic fuel, yet ATP, the molecule neurons use as an immediate source of energy, declined.

The discovery challenges the simple assumption that delivering more fuel to the brain should immediately increase its usable energy. Instead, REM sleep may place such intense or unusual demands on neural circuits that energy consumption briefly outpaces production, even as the brain prepares additional resources.

The findings were published in Communications Biology.

“Ever felt exhausted after a vivid dream?” asks Professor Ko Matsui of Tohoku University. “Sleep may appear peaceful, but the brain is highly active, especially when dreaming. We were intrigued by this paradox and wanted to look into the scientific basis behind why dreaming is somehow tiring.”

The brain energy paradox during REM sleep. During REM sleep, astrocytic pyruvate levels increased along with the increase in local brain blood volume (left). In contrast, when neuronal ATP was measured with a fluorescent sensor, neuronal ATP decreased despite the increase in local brain blood volume (right). These findings suggest that, during REM sleep, increased energy supply does not simply lead to increased neuronal ATP. Instead, energy flow appears to be dynamically reorganized among blood vessels, astrocytes, and neurons. 

Credit: Yusuke Takahashi, Yoko Ikoma, Ko Matsui

Why Dreaming Demands So Much

REM sleep is sometimes called “paradoxical sleep.” Brain activity can resemble wakefulness, the eyes move rapidly beneath closed lids, and vivid dreams are common, yet most skeletal muscles become deeply relaxed. REM sleep has also been linked to memory processing, emotional regulation, and communication between distant brain regions, although its precise functions remain under debate.

To watch metabolism shift during natural sleep, the researchers coated the skulls of mice with a transparent UV-curable resin. This allowed them to observe much of the cortex without removing part of the skull, a procedure that can disturb blood vessels and supporting brain cells.

Using wide-field fluorescence imaging, the team tracked three parts of the brain’s energy system. Blood volume provided an indication of incoming fuel, pyruvate in astrocytes reflected the processing of glucose, and ATP revealed how much immediately usable energy was available inside neurons.

Astrocytes are positioned between blood vessels and neurons, making them important metabolic intermediaries. They absorb glucose from the bloodstream and convert it into substances that can be used to produce ATP. Their location also allows them to help match blood flow and energy delivery to the changing demands of neural activity.

Blood Flow Prepares for REM

During non-REM sleep, the researchers detected a close relationship between brain activity and circulation. Small fluctuations in theta frequency activity predicted changes in cortical blood volume about four to five seconds later. The result suggests that even during deeper sleep, blood vessels continue adjusting their behavior to match changing neural and metabolic needs.

Brain blood volume dynamics reorganize during the transition to REM sleep. During NREM sleep, fast local brain blood volume fluctuations propagated from anterior to posterior cortex in about 1 second (left). During the transition to REM sleep, local brain blood volume began to rise about 50 seconds before the ECoG-defined REM onset (center). This increase started in posterior cortex and spread anteriorly over about 15 seconds (right), suggesting that REM sleep is preceded by a posterior-to-anterior metabolic preparation process involving vascular responses. 

Credit: Yusuke Takahashi, Yoko Ikoma, Ko Matsui

The approach to REM sleep was dramatically different. Blood volume began rising roughly 50 seconds before REM sleep officially started. The increase appeared first in the rear of the cortex and then moved forward, indicating that the brain may begin preparing for the energy demands of REM well before conventional measurements identify the transition.

Once REM sleep began, pyruvate increased inside astrocytes. That pattern suggested that more metabolic material was becoming available or that astrocytes were breaking down more glucose. Yet ATP inside neurons moved in the opposite direction and fell.

Why Neuronal Energy Falls

The researchers do not yet know why. Neurons may burn through ATP as circuits reorganize, memories are processed, and communication increases between regions such as the hippocampus and cortex. Another possibility is that the transfer of metabolic fuel from astrocytes to neurons changes during REM sleep. The neurons’ mitochondria, which produce most cellular ATP, may also temporarily shift how they operate.

The decline does not necessarily mean that neurons are being deprived of energy. ATP levels reflect the balance between production and consumption. A falling concentration could therefore signal that neurons are using ATP faster than they can replace it during this unusually active sleep state.

Brain waves predict local brain blood volume fluctuations during NREM sleep. Through-skull fluorescence imaging visualizes cerebral blood vessels as dark “shadows,” allowing local brain blood volume dynamics to be estimated (left). During NREM sleep, theta-band brain activity closely matched local brain blood volume changes occurring about 4 seconds later (center). Vascular responses appear to be dynamically adjusted to neuronal activity, supporting on-demand energy supply (right). 

Credit: Yusuke Takahashi, Yoko Ikoma, Ko Matsui

The results also show why blood flow alone cannot reveal how much usable energy neurons possess. More blood reached the brain, and astrocytes accumulated more pyruvate, but neither change translated into higher neuronal ATP. Energy delivery, processing, transfer, production, and consumption appear to be regulated separately rather than moving together.

This flexible system may help explain how the brain performs extraordinary amounts of computation while consuming relatively little power. The adult human brain is estimated to operate on roughly 20 watts, comparable to a dim light bulb, despite continuously controlling perception, memory, movement, emotion, and internal body functions.

How REM Sleep Supports Brain Efficiency

Rather than distributing energy evenly, the brain may redirect resources according to its current needs. During REM sleep, it could prioritize selected networks involved in internal processing while temporarily changing how fuel moves among blood vessels, astrocytes, and neurons.

“Understanding how the brain balances energy supply and consumption may help explain what makes biological intelligence so efficient,” explains lead investigator Yusuke Takahashi. “REM sleep gives us a natural example of how the brain reorganizes its energy economy to support complex internal processing.”

By revealing a hidden metabolic shift during REM sleep, the findings offer a new way to investigate how sleep supports memory and how the brain remains remarkably efficient.

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A Massive Study Reveals the Brain Is Far More Flexible Than We Thought

By The Zuckerman Inst. at Columbia U.August 1, 2026

https://scitechdaily.com/a-massive-study-reveals-the-brain-is-far-more-flexible-than-we-thought/

Neurons become less specialized as information moves into higher-order regions of the cortex. This unexpected diversity may reveal how populations of brain cells encode complex situations without relying on rigid, easily labeled roles.

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A single neuron may help the brain recognize what it sees, track what the body is doing, and guide a decision, all at the same time.

Most neurons may be far more versatile than scientists once thought. In a major study published in Nature, researchers analyzed more than 14,000 individual neurons across 43 regions of the mouse cortex and found that most did not perform one clearly defined job. Instead, they responded to shifting combinations of sensory information, movement, and decision-making.

The findings attracted unusual attention even before publication, with preliminary versions downloaded more than 11,000 times. The attention underscores a fundamental question in neuroscience: Are neurons dedicated specialists, or can individual brain cells participate in many different processes?

The answer appears to depend on where a neuron is located. Strong specialists were found in primary sensory regions, including areas that process visual information. But as signals moved into brain regions involved in more complex processing, neurons became increasingly difficult to sort into distinct functional groups.

Why the Brain Defies Simple Labels

In most of the cortex, the researchers found a diverse population of neural generalists.

“We have to move away from this image of the brain as a machine made of gears, with every gear having an exact purpose that we can attach a label to,” said Stefano Fusi, PhD, a principal investigator at Columbia’s Zuckerman Institute, a member of the Kavli Institute for Brain Science and the paper’s co-senior author. “The brain doesn’t work like that. Instead, most neurons can display a huge diversity of responses, and this can help the brain solve a huge number of different tasks.”

The discovery challenges a familiar way of describing the brain. Scientists often speak of neurons that respond to faces, locations, movements, or other particular features. Such labels can be useful, but the new findings suggest they may capture only one part of what a cell does.

A neuron that appears devoted to one feature under certain conditions may also encode several other pieces of information. Its activity might reflect what an animal sees, which choice it is considering, how it moves, and whether it expects a reward.

That flexibility could help explain how the brain handles new situations without requiring a separate group of cells for every possible experience.

Resolving a Long-Running Neuroscience Debate

Whether neurons are specialists or generalists “is an old, important question, and one which researchers have really strong opinions on,” said Lorenzo Posani, PhD, the study’s co-lead author and a principal investigator at the Paris Brain Institute and France’s CNRS. Posani conducted the work while at Columbia’s Zuckerman Institute.

The debate has remained unresolved partly because neuroscience experiments are often difficult to compare. Different laboratories may study different animals, brain regions, behaviors, or recording methods. One experiment might reveal neurons that appear highly specialized, while another finds cells responding to several unrelated variables.

The new study reduced those inconsistencies by examining a massive standardized dataset from the International Brain Laboratory. The recordings followed mice performing the same decision-making task while researchers measured individual neurons across dozens of cortical regions.

This allowed the team to compare neural activity across much of the cortex under the same conditions rather than piecing together results from unrelated experiments.

Specialists Become the Exception

The pattern was clear. Neurons near the beginning of the brain’s processing hierarchy tended to have more defined roles. Visual neurons, for example, were more likely to respond consistently to particular sensory features.

Farther along the hierarchy, those clean divisions largely disappeared. Neurons became more varied, with each cell responding to a different mixture of information. The cortex appeared to favor diversity over a rigid system of narrowly defined cell types.

“We’re not saying that there are no specialized neurons,” said Fusi, who is also a professor of neuroscience at Columbia’s Vagelos College of Physicians and Surgeons and a member of Columbia’s Center for Theoretical Neuroscience. “We’re saying they are the exceptions. They’re not the rule.”

Organized Brain Regions, Diverse Neurons

Despite this diversity, the activity was not random.

The researchers could often determine which brain region a neuron came from simply by examining its responses during the task. Cells within the same region shared broad characteristics, even though individual neurons rarely behaved in precisely the same way.

“For example, compare this to maps of voter opinions,” Posani said. “There are clear clusters where people generally vote the same way. But when you zoom in, you see mixes of opinions.”

The same principle appeared across the cortex. Brain regions remained distinguishable at the population level, but their individual neurons showed a wide range of response patterns.

The researchers also found that individual neurons rarely responded in exactly the same way.

A Flexible, High-Dimensional Brain Code

“Each is versatile in its own way,” said study co-lead author Shuqi Wang, a doctoral student at École Polytechnique Fédérale de Lausanne in Switzerland.

This diversity may be one of the brain’s strengths. If thousands of neurons responded identically, much of their activity would be redundant. By encoding different combinations of information, a population can represent far more possibilities.

Consider an animal viewing objects that differ in color and shape. Some neurons might respond mainly to color, while others reflect shape, movement, choice, or a combination of those variables. Together, their activity could distinguish a red circle from a red square, a black circle, or many other possibilities.

Neuroscientists describe these complex population patterns as “high-dimensional” representations. Rather than storing each feature separately, groups of neurons encode many overlapping variables at once. This creates a flexible neural code that can separate similar situations and support different behaviors.

“You can reuse these high-dimensional representations for lots of different tasks,” Fusi said.

Why Single Neurons Can Be Misleading

An individual neuron may respond to several variables, making its activity look confusing or inconsistent when viewed alone. The underlying information becomes clearer only when researchers examine the coordinated patterns produced by large populations of cells.

That idea marks a shift from decades of research that often searched for neurons with simple, easily labeled responses while setting aside cells that did not fit an obvious category.

Fusi said the field historically focused “on one neuron at a time, discarding all neurons whose responses could not be understood.”

The apparently messy activity of those cells may not have been meaningless. It may have reflected a richer and more adaptable form of information processing than researchers could detect with older approaches.

New Clues to Brain Disorders

Understanding this population code could eventually help scientists investigate what changes when brain networks malfunction. Neurological and psychiatric disorders may not always involve the failure of a single specialized cell type. Some could instead arise when patterns across large groups of versatile neurons lose their organization, flexibility, or ability to separate information.

The researchers also want to determine whether neurons shift between specialist and generalist behavior depending on the task. A cell that responds broadly in one situation might take on a narrower role when the brain faces a different demand.

“There is still a lot to discover,” Fusi said.

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Study Finds a Surprising Link Between Gut Microbes and Aging

By U. of Hawaii at Manoa, August 1, 2026

https://scitechdaily.com/study-finds-a-surprising-link-between-gut-microbes-and-aging/

Certain gut bacteria may act as subtle markers of biological aging, offering new clues about longevity and resilience. 

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Certain gut bacteria were linked to slower or faster biological aging.

The communities of bacteria living in the gut may carry clues about how rapidly the body is aging. Researchers at the University of Hawaiʻi at Mānoa found that certain microbial patterns were associated with faster or slower biological aging, adding to evidence that gut health is connected to longevity.

Published in Scientific Reports, the study found that variation in gut bacteria accounted for about 15% of the differences in participants’ biological aging rates. The results indicate that the gut microbiome contains measurable information about aging processes occurring at the molecular level.

“This study advances our understanding of the relationship between the gut microbiome and biological aging,” said senior author Alika K. Maunakea of the UH Mānoa John A. Burns School of Medicine. “We found that microbial patterns in the gut were significantly associated with molecular measures of aging, even independent of chronological age. These findings open important new directions for understanding how modifiable biological systems influence long-term health trajectories and longevity.”

Blood and stool reveal aging patterns
Researchers examined stool and blood samples from 123 adults spanning a wide range of ages. They compared the bacteria present in each participant’s gut with blood-based biomarkers designed to estimate the body’s rate of aging. Chronological age simply counts the years a person has lived, while biological aging measures are intended to reflect how quickly the body is changing physiologically.

Alika K. Maunakea, professor at the UH Mānoa John A. Burns School of Medicine, is a senior author of a study that found that certain gut bacteria are associated with the pace of biological aging. The research adds to growing evidence that the gut microbiome may play an important role in long-term health and healthy aging. 

Credit: University of Hawaii

Gut microbial composition was specifically associated with DunedinPACE, a next-generation biomarker that measures the pace of biological aging. Several bacterial species showed especially strong relationships with aging patterns. Bifidobacterium adolescentis was among the clearest microbial signatures associated with slower aging, while Succinivibrio dextrinosolvens had one of the strongest associations with faster aging.
Gut microbes may reflect resilience

Lead author Braden P. Kunihiro said the results demonstrate why the gut microbiome is attracting greater attention in precision health research.

“The gut microbiome is highly responsive to lifestyle, diet, environment and other everyday exposures,” Kunihiro said. “Our findings suggest that the microbiome may reflect important aspects of biological resilience and aging in ways that could eventually help inform future wellness and healthy aging strategies.”

This research adds to growing evidence that the gut microbiome may play an important role in long-term health and healthy aging. 

Credit: University of Hawaii

Native Hawaiian and Pacific Islander participants were also included in the research, helping represent populations that have historically been overlooked in studies of aging and the microbiome. Co-author Ruben Juarez said the findings could help clarify how social conditions and environmental exposures leave lasting biological effects.

“The microbiome exists at the intersection of behavior, environment and human biology,” Juarez said. “Studies like this help illuminate potential pathways through which lived experiences and social factors influence long-term health outcomes.”

The association does not prove cause

The researchers cautioned that the observed relationship does not demonstrate that gut bacteria directly control the pace of aging. Additional studies will be needed to determine whether deliberately changing the microbiome can influence how quickly the body ages.

“This is an important early step toward understanding the gut microbiome’s relationship with healthy aging,” Maunakea said. “Future research will help clarify the mechanisms involved and whether these microbial signatures may eventually contribute to precision approaches for promoting long-term health and wellness.”

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Feeling Lonely May Take a Bigger Toll on Health Than Expected

By U. of Bristol, July 23, 2026

https://scitechdaily.com/feeling-lonely-may-take-a-bigger-toll-on-health-than-expected/

Loneliness and social isolation may affect health in different ways, with the strongest signals emerging for mental health and well-being.

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Loneliness appears closely tied to poorer mental health, well-being and overall health.

Feeling lonely is closely associated with poorer mental health, reduced well-being and worse overall health, according to collaborative research led by the University of Bristol, Nesta and Amsterdam UMC. Social isolation was also linked to lower well-being, while loneliness was associated with having multiple health conditions.

Loneliness is increasingly viewed as a public health concern as evidence connecting it with poor health continues to grow. A central question remains unresolved, however: does loneliness itself contribute to declining health, or do other underlying factors explain the relationship?

Three methods strengthen the evidence

Working with researchers from the universities of Oxford and Manchester, the group approached the question through three complementary methods: observational analysis, comparisons between siblings and Mendelian randomization, a genetics-based technique used to investigate possible causal relationships.

The researchers drew on the UK Biobank and large-scale genome-wide association studies to examine two related but distinct experiences. Loneliness reflects the perceived quality of a person’s relationships, while social isolation describes the number of social connections they have. The findings were published in Nature Communications.

Mental health shows the clearest link

Across the analyses, both loneliness and social isolation were connected with poorer mental health and lower well-being. Loneliness was also associated with worse general health.

The study did not provide clear evidence that either experience affected particular physical health conditions. However, the researchers caution that such effects cannot yet be excluded.

Taken together, the results support treating loneliness, and potentially social isolation, as public health concerns because of their relationships with mental health, well-being and general health.

Loneliness becomes a public health priority

As loneliness receives greater recognition as a public health challenge, efforts to address it could benefit individuals as well as society more broadly.

Dr. Zoe Reed, Research Fellow in the School of Psychology and Neuroscience at the University of Bristol, and corresponding author, said: “Our findings suggest that loneliness, and possibly social isolation, are still important public health concerns, especially for mental health and general health. Supporting people who feel lonely or socially isolated could help improve mental health, well-being and overall health.”

Lauren Bowes Byatt, Director of Nesta’s healthy life mission, added: “This research underlines that loneliness is likely to have a detrimental impact on our mental health and well-being. While this link may seem obvious, the topic has long been understudied. Studies like this can help to bridge this research gap, and by understanding how loneliness or social isolation may be contributing to ill-health, we can get closer to new and more effective solutions.”

Long-term effects remain uncertain

Further research is needed to clarify how loneliness and social isolation influence health and to identify the most effective ways of reducing their effects.

Because the study examined middle-aged and older adults, future work will need to determine whether the same patterns appear among younger people. Researchers must also investigate persistent or long-term loneliness, since participants’ loneliness was measured at only one point in time.

The findings add to evidence that loneliness and social isolation extend beyond the social sphere. Their links with well-being and mental and physical health make them important considerations for public health policy and practice.

The birth of modern Man

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