The study, featured on the Dec. 4 cover of the journal Science Advances, used stable isotope analysis to model the diet of the mother of an infant discovered at a 13,000-year-old Clovis burial site in Montana. Before this study, prehistoric diet was inferred by analyzing secondary evidence, such as stone tools or the preserved remains of prey animals.

The findings support the hypothesis that Clovis people specialized in hunting large animals rather than primarily foraging for smaller animals and plants.

The Clovis people inhabited North America around 13,000 years ago. During that time period, animals like mammoths lived across both northern Asia and the Americas. They migrated long distances, which made them a reliable fat- and protein-rich resource for highly mobile humans.

“The focus on mammoths helps explain how Clovis people could spread throughout North America and into South America in just a few hundred years,” said co-lead author James Chatters of McMaster University.

“What’s striking to me is that this confirms a lot of data from other sites. For example, the animal parts left at Clovis sites are dominated by megafauna, and the projectile points are large, affixed to darts, which were efficient distance weapons,” said co-lead author Ben Potter, an archaeology professor at the University of Alaska Fairbanks.

Hunting mammoths provided a flexible way of life, Potter said. It allowed the Clovis people to move into new areas without having to rely on smaller, localized game, which could vary significantly from one region to the next.

“This mobility aligns with what we see in Clovis technology and settlement patterns,” Potter said. “They were highly mobile. They transported resources like toolstone over hundreds of miles.”

Researchers were able to model the Clovis people’s diet by first analyzing isotopic data published during earlier studies by other researchers of the remains of Anzick-1, an 18-month-old Clovis child. By adjusting for nursing, they were able to estimate values for his mother’s diet.

“Isotopes provide a chemical fingerprint of a consumer’s diet and can be compared with those from potential diet items to estimate the proportional contribution of different diet items,” said Mat Wooller, an author on the study and director of the Alaska Stable Isotope facility at UAF.

The team compared the mother’s stable isotopic fingerprint to those from a wide variety of food sources from the same time period and region. They found that about 40% of her diet came from mammoth, with other large animals like elk and bison making up the rest. Small mammals, sometimes thought to have been an important food source, played a very minor role in her diet.

Finally, the scientists compared the mother’s diet to those of other omnivores and carnivores from the same time period, including American lions, bears and wolves. The mother’s diet was most similar to that of the scimitar cat, a mammoth specialist.

Findings also suggest that early humans may have contributed to the extinction of large ice age animals, especially as environmental changes reduced their habitats.

“If the climate is changing in a way that reduces the suitable habitat for some of these megafauna, then it makes them potentially more susceptible to human predation. These people were very effective hunters,” said Potter.

“You had the combination of a highly sophisticated hunting culture — with skills honed over 10,000 years in Eurasia — meeting naïve populations of megafauna under environmental stress,” said Chatters.

An important aspect of this research, according to Potter and Chatters, is their outreach to Native Americans in Montana and Wyoming about their concerns and interest in this work.

“It is important and ethical to consult with Indigenous peoples on questions relating to their heritage,” they said.

They worked with Shane Doyle, executive director of Yellowstone Peoples, who reached out to numerous tribal government representatives throughout Montana, Wyoming and Idaho. “The response has been one of appreciative consideration and inclusion,” said Doyle.

“I congratulate the team for their astounding discovery about the lifeways of Clovis-era Native people and thank them for being tribally inclusive and respectful throughout their research,” he said. “This study reshapes our understanding of how Indigenous people across America thrived by hunting one of the most dangerous and dominant animals of the day, the mammoth.”

Other authors of the paper include Stuart J. Fiedel, independent researcher; Juliet E. Morrow, University of Arkansas; and Christopher N. Jass, Royal Alberta Museum.

Guided by previous research of spider brains, the scientists uncovered evidence of a “waste canal system” in the human brain that internalizes waste from healthy neurons. They discovered that this system can undergo catastrophic swelling, which leads to the degeneration of brain tissue, a hallmark of Alzheimer’s disease.

With over 50 million affected people worldwide, Alzheimer’s disease is among the leading causes of death in the U.S.

The findings, which have been published by The Journal of Comparative Neurology, offer a compelling new explanation for commonly described brain pathologies observed in Alzheimer’s disease, including amyloid-beta plaques, tau tangles, and spongiform abnormalities.

Supported by the Vermont Biomedical Research Network (VBRN), the research was carried out in collaboration among Dr. Ruth Fabian-Fine (Saint Michael’s College, UVM Robert Larner, M.D. College of Medicine), Dr. John DeWitt (UVM Robert Larner, M.D. College of Medicine, UVM Medical Center), Dr. Adam Weaver (Saint Michael’s College), and Saint Michael’s undergraduate research students Abigail Roman and Melanie Winters, both members of the Class of 2025.

“The Vermont Biomedical Network has been thrilled to support Dr. Fabian-Fine’s research from its initial focus on animal neuroscience to the more recent and potentially groundbreaking emphasis on the cellular basis of human neurodegeneration,” said UVM’s Dr. Christopher Francklyn, the Director of VBRN. “Her exciting work, and the outstanding training she has provided to her undergraduate co-investigators, epitomizes what NIH hopes to accomplish with its national IDEA program.”

Neuroscientist Dr. Fabian-Fine and her team initially investigated the underlying causes for neurodegeneration in Central American wandering spiders that suffer from conditions similar to degenerative diseases in humans. Because the spider neurons were a larger size, the scientists were better able to observe their brain functions. They quickly discovered a waste-internalizing glial canal system that undergoes structural abnormalities in degenerating spider brains, which leads to uncontrolled depletion and death of brain cells.

This discovery prompted Fabian-Fine, a Vermont Center for Cardiovascular and Brain Health Pipeline Investigator, to explore whether a similar system could be found in both rodent and human brain tissue, so she teamed up with neuropathologist Dr. DeWitt at UVM’s Larner College of Medicine. The collaborative undertaking led the scientists to gather overwhelming evidence that neurodegeneration in human and rodent brains may have similar underlying causes compared to those observed in spider brains. The scientists’ report outlines possible underlying causes for neurodegeneration that may offer a promising new avenue for drug development that can address the structural abnormalities that lead to neurodegeneration.

Dozens of student researchers at Saint Michael’s College contributed to the multi-year research that provided the foundation for this breakthrough. Experiments occurred at Saint Michael’s College, the University of Vermont Medical Center, and at the UVM’s Center for Biomedical Shared Resources.

Further, the results of the study by Oregon Health & Science University involving neurosurgery patients suggests new possibilities for tapping into those areas to improve learning among people bedeviled by math.

“This work lays the foundation to deeper understanding of number, math and symbol cognition — something that is uniquely human,” said senior author Ahmed Raslan, M.D., professor and chair of neurological surgery in the OHSU School of Medicine. “The implications are far-reaching.”

The study published today in the journal PLOS ONE.

Raslan and co-authors recruited 13 people with epilepsy who were undergoing a commonly used surgical intervention to map the exact location within their brains where seizures originate, a procedure known as stereotactic electroencephalography. During the procedure, researchers asked the patients a series of questions that prompted them to think about numbers as symbols (for example, 3), as words (“three”) and as concepts (a series of three dots).

As the patients responded, researchers found activity in a surprising place: the putamen.

Located deep within the basal ganglia above the brain stem, the putamen is an area of the brain primarily associated with elemental functions, such as movement, and some cognitive function, but rarely with higher-order aspects of human intelligence like solving calculus. Neuroscientists typically ascribe consciousness and abstract thought to the cerebral cortex, which evolved later in human evolution and wraps around the brain’s outer layer in folded gray matter.

“That likely means the human ability to process numbers is something that we acquired early during evolution,” Raslan said. “There is something deeper in the brain that gives us this capacity to leap to where we are today.”

Researchers also found activity as expected in regions of the brain that encode visual and auditory inputs, as well as the parietal lobe, which is known to be involved in numerical and calculation-related functions.

From a practical standpoint, the findings could prove useful in avoiding important areas during surgeries to remove tumors or epilepsy focal points, or in placing neurostimulators designed to stop seizures.

“Brain areas involved in processing numbers can be delineated and extra care taken to avoid damaging these areas during neurosurgical interventions,” said lead author Alexander Rockhill, Ph.D., a postdoctoral researcher in Raslan’s lab.

Researchers credited the patients involved in the study.

“We are extremely grateful to our epilepsy patients for their willingness to participate in this research,” said co-author Christian Lopez Ramos, M.D., a neurosurgical resident at OHSU. “Their involvement in answering our questions during surgery turned out to be the key to advancing scientific understanding about how our brain evolved in the deep past and how it works today.”

Indeed, the study follows previous lines of research involving mapping of the human brain during surgery.

“I have access to the most valuable human data in nature,” Raslan said. “It would be a shame to miss an opportunity to understand how the brain and mind function. All we have to do is ask the right questions.”

In the next stage of this line of research, Raslan anticipates discerning areas of the brain capable of performing other higher-level functions.

In addition to Raslan, Rockhill and Lopez Ramos, co-authors include Hao Tan, M.D., Beck Shafie, Maryam Shahin, M.D., Adeline Fecker, Mostafa Ismail, Daniel Cleary, M.D., and Kelly Collins, M.D., of OHSU; and Caleb Nerison, D.O., now of Lexington Medical Center in South Carolina.

Combining two materials that selectively absorb short and long wavelengths, e.g., blue/green and red/infrared parts of the spectrum, makes the best use of our sunlight and is a well-known strategy to increase efficiency in solar cells. Best red/infrared absorbing parts of solar cells so far were, however, made from traditional materials, such as silicon or CIGS (copper indium gallium selenide). Unfortunately, these require high processing temperatures, and thus exhibit a relatively high carbon footprint.

In their work, now published in Nature, Lang and colleagues combine two emerging solar cell technologies, namely perovskite and organic solar cells, that both are processed at low temperatures with a low carbon footprint. Achieving a record level of 25.7 % efficiency for this new combination, however, was not easy, says Felix Lang: “This was only possible by combining two major breakthroughs.” First, Meng and Li synthesized a novel red/infrared absorbing organic solar cell that extends its absorption even further into the infrared. “Still, tandem solar cells were limited by the perovskite layer, which shows strong efficiency losses if adjusted to absorb only blue/green parts of the sun spectrum,” he explains. “To tackle this, we utilized a novel passivation layer applied to the perovskite that reduces material defects and improves the performance of the whole cell.”