Mammals and dinosaurs coexisted on Earth until . Despite the devastation, some animals survived, including rodent-like mammals in the Cimolodon genus. These creatures are part of , a group that arose during the Jurassic Period and survived over 100 million years before going extinct. Studying these animals helps researchers better understand how mammals survived the mass extinction event and then diversified into the variety of mammals around today.

A research team led by the �������� has identified a new species in the Cimolodon genus from a fossil the team discovered at a research site in Baja California. The researchers estimate that this fossil is about 75 million years old. The new species, named Cimolodon desosai, was about the size of a golden hamster, the researchers said. It likely scampered on the ground and in trees and ate fruits and insects.

The researchers April 22 in the Journal of Vertebrate Paleontology.

“The genus Cimolodon was a pretty common mammal during the Late Cretaceous, the last epoch of the Age of Dinosaurs. Cimolodon fossils have been found throughout western North America, from western Canada down through Mexico,” said senior author , a UW professor of biology and curator of vertebrate paleontology at the Burke Museum. “This new species, Cimolodon desosai, was ancestral to the species that survived the extinction event. It and its descendants were relatively small and omnivorous — two traits that were advantageous for surviving.”

When Wilson Mantilla and his team discovered the fossil in 2009, they found teeth, a skull, jaws and parts of the skeleton, including a femur and an ulna.

“It’s very hard to find fossils at this site compared to other areas,” Wilson Mantilla said. “At first, my field assistant found just a little tooth poking out. If he had just found that, I would have been over the moon. But then when we looked inside the crack of the rock, we could see there was more bone.”

The fact that the researchers uncovered more than just teeth for C. desosai means that they can better understand its size and shape and how it likely moved. It also helps fill out the picture of this genus and the habitat in which it lived, and contributes to a better understanding of the multituberculate group in general.

The researchers used digital imaging and a tool called micro-computed tomography, or micro-CT, to get high resolution images of the fossil. Then the team compared the teeth of C. desosai to those of its cousins in the Cimolodon genus to establish it as a new species.

“That far back in time everything is named based on their tooth characteristics,” Wilson Mantilla said. “If you find a skeleton that’s missing teeth, sometimes it’s hard to attach it to a name.”

The team named this species after Michael de Sosa VI, the field assistant who first found it, because de Sosa died while they were still analyzing the fossil.

“He was a great field assistant, and he was like a little brother to me,” Wilson Mantilla said. “It’s a great specimen to be associated with.”

Additional co-authors are , UW doctoral student in biology, at the University of Rhode Island; Yue Zhang, who completed this research as a UW postdoctoral fellow in biology; Meng Chen, who completed this research as a UW doctoral student in biology; and and at the Universidad Nacional Autónoma de México.

This research was funded by UC MEXUS-CONACYT, Dirección General de Asuntos del Personal Académico PAPIIT IN111209-2, the UW College of Arts and Sciences, the UW Department of Biology and the American Philosophical Society.

For more information, contact Wilson Mantilla at gpwilson@uw.edu.

As far as research subjects go, it’s not always easy to find common ground with a single-celled bacterium. Yet the more studies his model bacteria, , the more he sees surprising commonalities between their behavior and our own as humans.

“It was mortifying to be stumped for so long by what appeared to be completely counterintuitive behavior only to realize that I engage in exactly the same behavior everyday,” said Wiggins, an associate professor of both physics and bioengineering at the ��������.��

Scientists in use experiments and modeling to understand the global principles that govern gene expression, and protein abundance in particular. In in Science Advances, Wiggins’ team discovered that A. baylyi cells amass huge surpluses of essential proteins, rather than taking the seemingly more efficient approach of making just enough to survive. UW News chatted with Wiggins to learn about the remarkably relatable reason for this puzzling behavior.

This work grew out of a mystery you and your team uncovered. Tell us about that mystery.

Paul Wiggins: Genes are the blueprints for proteins — we say they “code for proteins.” A. baylyi has a number of genes that code for proteins that we know are essential for cell growth. But we didn’t know exactly what each of these proteins do. In 2016, we were attempting to uncover these proteins’ specific functions in collaboration with the . To do this we disrupted each gene so that the cells couldn’t make any more protein — they were left with a now dwindling supply of whatever they’d previously made. Then we would watch the cells under a microscope to determine when and how cellular processes would fail.��

As an example, we knocked out a gene that coded for a protein that we found was responsible for cell wall synthesis — it makes the protein-sugar chainmail that prevents the cells from rupturing, or lysing. And you can watch the video we recorded to see what happened: The cells grew and divided for a while, but then all of a sudden they inflated and just popped.

In that example, something strange happened. We would expect the cell walls to start to fail almost immediately after the disruption happened because every time the cells divide, the remaining protein is divided among the offspring cells, so pretty quickly there wouldn’t be enough to sustain the new cell walls. However, growth continued, one generation after another, before the cells finally failed after four rounds of division!

Why did it take so long? Gene after gene showed the same pattern. We realized that each cell must have made a ton of extra proteins — far more than it needed. So after we knocked out that essential gene, the cell was able to run on fumes for a while — and was even able to pass stores of that protein on to its offspring. That finding was initially a huge surprise. We all expected, naively, that if a cell only needed a few copies of a protein to function, it would only make a few — anything more would be a waste of resources and energy. It’d be like taking a seven-day trip and packing 30 pairs of socks. And yet, this behavior seemed to be common for lots of essential genes.��

What do you think is the cause of this protein overabundance?

PW: Baking is a good analogy. If you want to make an apple pie, you probably only buy as many apples as you need for that recipe. But you keep a large quantity of salt in your pantry. You might only need a teaspoon of salt to make any given meal, but none of us go to the store and buy salt a teaspoon at a time. Salt is so cheap and easy to store that, relative to the cost of other ingredients in your meal, it’s basically free to keep in large quantities. And critically, you don’t want to run out of salt when you’re cooking.��

We demonstrated that something analogous is happening in A. baylyi cells for most of the essential genes. Only about 30% of a cell’s essential genes code for proteins that are “expensive” in that the cells need these proteins in large numbers. It would be very costly to, say, double an already large number. These are the apples in our apple pie analogy — the cell makes just enough of those proteins to get by.��

The remaining 70% of essential genes, however, code for proteins that the cell does not need in large numbers. In fact, relative to that other 30%, the cell needs so few of these proteins that it’s basically free to produce a bunch of extras. Doubling the production of those proteins, say from 30 to 60 copies, is a drop in the bucket if the cell’s overall budget is three million proteins. So the cell says, “Screw it, it’s virtually free. Let’s make extra so we don’t run out.” In some cases a cell might make 10 times more protein than it will ever need.

Why is this strategy useful for the cells?

PW: This overabundance strategy is important because otherwise a cell might fail to produce enough of something critical. Protein synthesis is an imprecise process — cells sometimes make a little more or a little less of things than they’re programmed to make. Some essential proteins are made at such low numbers that any deviation from the plan could leave a cell with zero copies of that protein. This is less of a problem for essential proteins that are made in much higher numbers.��

How do these findings support or challenge previous ideas about how cells function?

PW: Depending on who you talk to, this is either definitely wrong or completely obvious. On the one hand, it’s a really ingrained idea that organisms are always optimizing everything, which would naively suggest that cells should make exactly what they need — no more, no less. However, this is clearly not the case. Other studies have observed these kinds of protein surpluses in cells before, but it wasn’t appreciated quite how wide-spread this phenomenon was. Previously researchers proposed that overabundance might be a hedge against changing conditions — maybe cells are stockpiling proteins in case times get tough. We’re suggesting that it’s a hedge against the cells failing to make the right number of essential proteins.

Co-authors include , a UW postdoctoral researcher of physics; Teresa W. Lo and , former UW doctoral students of physics; , a UW graduate student of physics; and , a UW postdoctoral researcher of laboratory medicine and pathology.

This research was funded by the National Science Foundation and the National Institutes of Health.

For more information, contact Wiggins at pwiggins@uw.edu.��

�������� professor of physics and UW research professor emeritus are part of an international team that won the 2026 . The $3 million award is shared among roughly 400 scientists, including 18 other researchers from the UW team. It celebrates decades of work to better understand the muon — a subatomic particle with anomalous properties. This collaborative effort could ultimately lead to the discovery of entirely new particles.

“A remarkable aspect of these experiments is that it took the collective talents and experience of scientists and engineers from particle, nuclear, atomic, optical, accelerator and theoretical physics communities to work coherently toward one single goal,” Hertzog said. “Together, we measured a property of the muon that encapsulates almost everything we know about modern physics from relativity to quantum mechanics to the zoo of particles that govern the fundamental forces that shape our world.”

The were established in 2012 to recognize research achievements in life sciences, fundamental physics and mathematics.��

Muons, short-lived subatomic particles, are created for experiments by particle accelerators. They exist for a fraction of a second before decaying into electrons and even tinier particles called neutrinos. During their short life, muons exhibit magnetic properties that deviate slightly from the – the leading theory that describes the particles and forces that make up the universe, along with anything that exists that has not yet been discovered.

The experiments recognized by the Breakthrough Prize represent 60-plus years of work to find out exactly how far the muon’s magnetism strays from Standard Model predictions. The first experiments began in 1959 at the, also called CERN.��

Hertzog’s group at the University of Illinois was involved in a later experiment at the in the mid-1990s. He joined the faculty at UW in 2010 and helped develop a new experiment at (Fermilab) that in 2025 with record-setting precision.��

While Hertzog and others have now completed their experimental measurements, theorists�� continue to refine the predictions of the Standard Model. In time, the gap between theory and experiment — where the muon currently hovers — may vanish or persist. If the muon’s properties never fit the Standard Model, physicists may need to explore entirely new theories.��

“No matter where the final theory settles, the comparison with our experiment will have important consequences and give us deep insight into the heart of matter,” Hertzog said.

Many UW physicists have been recognized by Breakthrough Prizes since the prizes’ inception, including a banner year in 2021 that also featured a win in the life sciences category by Nobel Prize laureate , a UW professor of biochemistry.

“The Breakthrough Prize has previously recognized UW physicists for work that deepened our understanding of gravity, dark energy and dark matter,” said , UW divisional dean of natural sciences in the College of Arts and Sciences. “This latest recognition is a testament to the value of large-scale collaborative physics research and we are very proud of the accomplishments of all of the UW faculty, postdocs and students who contributed to this effort.”

A full list of current UW researchers recognized by the 2026 prize . Learn about other UW wins at the Breakthrough Prize here.��

For more information, contact Victor Balta at balta@uw.edu.

The �������� has been notified by the U.S. Department of Justice that it is conducting a compliance review. The University will cooperate with the review and provide information and responses.

The off-campus event referenced publicly appears to have been organized by a group falsely claiming affiliation with the ��������. That group’s registration was suspended in June 2024 and permanently revoked in May 2025. The �������� strongly and unequivocally opposes antisemitism in all forms.

We also notified Meta last year of this group’s unauthorized use of the University’s name on social media, and appealed Meta’s refusal to address this issue on March 10. That appeal is pending.

It took less than 22 years after the discovery of the hepatitis C virus (HCV) for a fast-acting, highly effective treatment to become available. at curing hepatitis C infection, yet the virus remains a critical public health problem. It’s the most common bloodborne illness in the United States, and disproportionately impacts low-income people and marginalized communities.��

A directive aimed to eliminate the disease from Washington state by 2030. The first-in-the-nation plan called for coordination between public health agencies, increased screening, removal of barriers to care and a new approach to purchasing antiviral medications at a discount.��

A new study led by the �������� found that the plan not only expanded access to tests and treatment, but may save money in the long run. , the study found that total costs for hepatitis C-related care rose when the program was first implemented but have declined since, even as increased screening identifies more cases.��

“Comprehensive health insurance claims data can help us see how patterns in testing, treatment and healthcare costs are changing over time across a large population,” said lead author , who worked on the study while completing a doctoral degree at the UW. “That kind of information can help states better understand how initiatives to expand access to care may affect both patients and the healthcare system.”

Working in collaboration with the Washington State Health Care Authority and the Washington State Department of Health, researchers analyzed medical claims data between January 2017 and September 2022. Records included medical and pharmacy claims collected from both private insurance companies and public payers. The data represented about 70% of Washington residents, approximately 6-8 million individuals per year.��

Researchers found that the number of HCV tests administered increased sharply after Washington implemented the elimination initiative. There was a median of 28,375 tests per month at the end of 2017, peaking at 99,161 by July 2020. The number of tests then leveled off at a median of 55,844 per month throughout 2021. Researchers noted that these shifts also aligned with new national guidelines that recommended all adults receive at least one HCV test. Consistent with increased screening, the study observed an initial increase in the total number of HCV cases, followed by a significant decline over time as more people received treatment.

The study also found that total HCV-related costs spiked immediately after implementation of the initiative, but then dropped closer to initial levels. Total monthly costs rose from $45.6 million in 2017 to $70.8 million in 2019, an increase the researchers attributed to expanded screening, which identified more cases to treat. Monthly costs then declined to $56.8 million in 2021.��

While total HCV care costs rose, costs per patient declined by more than 45%. Researchers said the decline may be due to increased screening catching more infections in otherwise healthy people, which would likely improve treatment outcomes and reduce associated risks over time.��

“As an observational study, we cannot directly attribute the changes over time to the state initiative,” said co-author , a professor of global health and of child, family and population health nursing at the UW. “However, it does support the idea that investing in screening and treatment of healthy people without symptoms is more cost-effective than waiting until they become sick.”��

Other authors include , professor of health economics and director of the Comparative Health Outcomes, Policy and Economics (CHOICE) Institute at the UW; , teaching professor of biobehavioral nursing and health informatics in the UW School of Nursing; , assistant professor of child, family and population health nursing and of allergy and infectious diseases at the UW School of Medicine; , research coordinator in the Department of Child, Family and Population Health Nursing at the UW; Judy Zerzan-Thul, Leta Evaskus, Donna Sullivan, Stella Chang and JoEllen Colson of the Washington State Health Care Authority; and Emalie Huriaux and Jon Stockton of the Washington State Department of Health.

This study was funded by the Laura and John Arnold Foundation.

The Ecological Society of America on Wednesday awards. , a �������� assistant professor of environmental and forest science, was named an Early Career Fellow, which recognizes scientists for contributions to advancing and applying ecological knowledge within eight years of completing a doctorate.

Willing studies how microbes respond, and help plants cope with, environmental change. focuses on fungi and other microbes living near plant roots. Much like the gut microbiome, these communities play a critical role in plant nutrition, immune function and overall forest health.

Willing’s lab focuses on understanding these communities and how they are shifting with climate change. Her research integrates methods from various scientific disciplines to gain insight into the ecosystem-wide impact of fungi.

“I work across pretty diverse fields, from fungal ecology to plant and forest ecology,” Willing said. “Integrating everything together is challenging, but I think it’s a critical intersection to study right now and this award is a nice acknowledgement of that.”

As a Faculty Fellow, Willing also collaborates with federal, state and tribal agencies to incorporate fungi into climate adaptation planning.

Many of her lab’s projects examine responses to climate change. For example, one of Willing’s current grad students is studying fungi in post-fire ecosystems.

Some fungal groups are fire-adapted, meaning that they can withstand wildfire better than others. After wildfire, the soil often becomes hydrophobic, which causes water to run off the surface instead of soaking in. This increases the risk of erosion, among other consequences. Fungi help seedlings to establish and stabilize the soil by helping it retain water.

Early findings from her lab indicate that prolonged fire suppression, a stewardship strategy intended to minimize wildfire impacts, can limit microorganisms fire tolerance, which then exacerbates the damage caused by a fire.

“There are lots of different nuances that we’re really just starting to understand,” Willing said.

She hopes this work can help inform future forest management practices. Although there are many mushroom enthusiasts in the Pacific Northwest, Willing is one of few scientists in the region studying how these organisms fold into broader ecosystems.

Most of the data on microbial communities was collected within the past 20 years or so, which makes it difficult to gauge how these organisms are responding to climate change. Another project in Willing’s lab involves conducting genetic analyses on preserved plant specimens to establish a baseline for fungal health.

“Our understanding of what fungal and bacterial communities were like before the onset of rapid warming is really limited,” Willing said.

Building this baseline will help researchers see how microbial communities are evolving and reveal management opportunities.

Without fungi, life on Earth couldn’t exist as we know it. Dead logs and fallen leaves would simply accumulate, with nothing to break them down and return their nutrients to the soil.

“Fungi are involved in everything,” Willing said. “In the cycle of life, they are at the beginning, helping plants to take root across every ecosystem on Earth, and at the end, helping to create lush soils for future life to flourish.”

ESA will acknowledge and celebrate fellows during a ceremony on July 27 at the annual meeting in Salt Lake City. Early Career Fellows are elected for five years.

For more information about her work, contact Willing at willingc@uw.edu.

Unfortunately for science fiction fans, desert worlds outside our solar system are unlikely to host life, according to new research from ��������. Scientists show that an Earth-sized planet needs at least 20 to 50% of the water in Earth’s oceans to maintain a critical natural cycle that keeps water on the surface.

Scientists believe that there are billions of planets outside our solar system. More than are confirmed, but only some of them are candidates for life. The search for life has focused on planets in the “,” a sweet spot that is neither too close nor too far from a central star. Planets in this zone are considered viable because they can maintain liquid surface water.

“When you are searching for life in the broad landscape of the universe with limited resources, you have to filter out some planets,” said lead author , a UW doctoral student of Earth and space sciences.

Water, although essential, does not guarantee the existence of life. With this study, researchers worked to further narrow the search by investigating planets with just a small amount of water.

“We were interested in arid planets with very limited surface water inventory — far less than one Earth ocean. Many of these planets are in the habitable zone of their star, but we weren’t sure if they could actually be habitable,” White-Gianella said.

The team’s results, , show that habitability hinges on the geologic carbon cycle — a water-driven process that exchanges carbon between the atmosphere and interior over millions of years, stabilizing surface temperatures.

Carbon dioxide, which comes from volcanoes in a natural system, accumulates in the atmosphere before falling back to Earth dissolved in rainwater. Rain erodes and chemically reacts with rocks on the Earth’s surface and runoff transports carbon to the ocean, where it sinks to the seafloor. Plate tectonics drives carbon-rich oceanic plates below continental land. Millions of years later, carbon resurfaces as mountains form.

If water levels drop too low for rainfall, carbon removal — from weathering — can’t keep up with emissions from volcanic eruptions and carbon dioxide levels in the atmosphere spike, trapping water. Rising temperatures evaporate the remaining surface water, initiating runaway warming that makes the planet too hot to support life.

“So that unfortunately makes these arid planets within habitable zones unlikely to be good candidates for life,” White-Gianella said.

Although scientists have instruments that can measure surface water, rocky exoplanets are difficult to observe directly. In this study, the researchers ran a series of complex simulations to better understand how water might behave in these desert worlds.

Previous efforts to model the carbon cycle focused on cooler, perhaps wetter planets. The models factored in evaporation from sunlight, but didn’t include other drivers, such as wind. White-Gianella adapted existing models to drier planets by refining evaporation and precipitation estimates.

“These sophisticated, mechanistic models of the carbon cycle have emerged from people trying to understand how Earth’s thermostat has worked — or hasn’t — to regulate temperature through time,” said senior author , a UW assistant professor of Earth and space sciences.

However, the function of the geologic carbon cycle on arid planets was largely unexplored. The results show that even planets that form with surface water could lose it, transitioning from potentially habitable to uninhabitable due to carbon cycle disruption.

One such planet exists far closer to home: Venus. The planet of love is roughly the same size as Earth, likely formed around the same time and may have started with a similar amount of water.

Yet today, the surface of Venus rivals the temperature of a wood-fired pizza oven. Standing on the surface would feel like being crushed by 10 blue whales, White-Gianella said.

Many theories attempt to explain why Earth and Venus are so different. White-Gianella and Krissanen-Totton propose that Venus, being closer to the sun, may have formed with slightly less water than Earth, which imbalanced the geologic carbon cycle. As surface temperatures rose with atmospheric carbon dioxide levels, Venus lost its water — and any life it may have hosted.

Upcoming missions to Venus will attempt to understand what happened to the planet and whether it ever hosted life. The findings could also offer insight into planets much farther away.

“It’s very unlikely that we will land something on the surface of an exoplanet in our lifetime, but Venus — our nextdoor neighbor — is arguably the best exoplanet analog,” White-Gianella said.

The researchers hope that results from future missions will help validate the results of their modeling.

“This has implications for a lot of the potentially habitable real estate out there,” Krissanen-Totton said.

This study was funded by the National Science Foundation, the NASA Astrobiology Program and the Alfred P. Sloan Foundation.

For more information, contact White-Gianella at hasktw@uw.edu or Krissanen-Totton at joshkt@uw.edu.��

The �������� has earned a Gold rating from the ​​Sustainability Tracking, Assessment & Rating System, or STARS.

The STARS ratings, administered by the Association for the Advancement of Sustainability in Higher Education, are good for three years and are based on self-reported assessments. The UW has held a Gold rating from STARS since first participating in 2012.

“The STARS Gold rating is recognition of all the hard work being done across our campus by staff, students and faculty for sustainability,” UW Sustainability director Lisa Dulude said. “As we celebrate Earth Day in April, this achievement is a reminder of the UW’s commitment to embed sustainability in everything we do, and the benefits of this work for our environment and our community.”

The STARS report covers the UW in Seattle and includes questions on sustainability performance in academics, planning and administration, engagement and operations. About 380 schools worldwide have active STARS ratings. Gold is the second-highest tier. There are 17 schools that have achieved the highest Platinum rating. UW Bothell also holds a STARS Gold rating.

All STARS reports are public, and the .

STARS is the most wide-reaching sustainability report, and the information collected gives the UW a comprehensive view of its sustainability performance and allows for comparison to peer universities. It can also provide insight on areas where additional efforts might be needed.

The information is used to inform the UW’s Sustainability Action Plan, which sets out the University’s sustainability goals. The first Sustainability Action Plan was adopted in 2020, and the UW is currently in the process of creating an updated Plan, which will be finalized by summer 2026.

“The UW has long been a sustainability leader in higher education, as evidenced by our long track record of STARS Gold ratings,” Dulude said. “With the Sustainability Action Plan update, working groups have identified several areas to set measurable targets, which ensure we will continue that leadership.”

The UW’s sustainability efforts are also on show in recognition of Earth Day on April 22. Events organized by a variety of groups across the UW happen throughout the month, including volunteer opportunities, workshops and more. You can see the on the UW Sustainability site.

�������� researchers developed the first system that incorporates tiny cameras in off-the-shelf wireless earbuds to allow users to talk with an AI model about the scene in front of them. For instance, a user might turn to a Korean food package and say, “Hey Vue, translate this for me.” They’d then hear an AI voice say, “The visible text translates to ‘Cold Noodles’ in English.”

The prototype system called VueBuds takes low-resolution, black-and-white images, which it transmits over Bluetooth to a phone or other nearby device. A small artificial intelligence model on the device then answers questions about the images within around a second. For privacy, all of the processing happens on the device, a small light turns on when the system is recording, and users can immediately delete images.��

The team will April 14 at the Association for Computing Machinery Conference on Human Factors in Computing Systems in Barcelona.��

“We haven’t seen most people adopt smart glasses or VR headsets, in part because a lot of people don’t like wearing glasses, and they often come with , such as recording high-resolution video and processing it in the cloud,” said senior author , a UW professor in the Paul G. Allen School of Computer Science & Engineering. “But almost everyone wears earbuds already, so we wanted to see if we could put visual intelligence into tiny, low-power earbuds, and also address privacy concerns in the process.”

Cameras use far more power than the microphones already in earbuds, so using the same sort of high-res cameras as those in smart glasses wouldn’t work. Also, large amounts of information can’t stream continuously over Bluetooth, so the system can’t run continuous video.��

The team found that using a low-power camera — roughly the size of a grain of rice — to shoot low-resolution, black-and-white still images limited battery drain and allowed for Bluetooth transmission while preserving performance.

There was also the matter of placement.��

“One big question we had was: Will your face obscure the view too much? Can earbud cameras capture the user’s view of the world reliably?” said lead author , who completed this work as a UW doctoral student in the Allen School.��

The team found that angling each camera 5-10 degrees outward provides a 98-108 degree field of view. While this creates a small blind spot when objects are held closer than 20 centimeters from the user, people rarely hold things that close to examine them — making it a non-issue for typical interactions.

Sixteen participants also wore VueBuds and tested the system’s ability to translate and answer basic questions about objects. VueBuds achieved 83-84% accuracy when translating or identifying objects and 93% when identifying the author and title of a book.

This study was designed to gauge the feasibility of integrating cameras in wireless earbuds. Since the system only takes grayscale images, it can’t answer questions that involve color in the scene.��

The team wants to add color to the system — color cameras require more power — and to train specialized AI models for specific use cases, such as translation.����

“This study lets us glimpse what’s possible just using a general purpose language model and our wireless earbuds with cameras,” Kim said. “But we’d like to study the system more rigorously for applications like reading a book — for people who have low vision or are blind, for instance — or translating text for travelers.”��

Co-authors include , a UW master’s student in the Allen School, and , , , and , all UW students in electrical and computer engineering.��

For more information, contact vuebuds@cs.washington.edu.

Weasels are small carnivores with a long body and short legs. They also have a stout skull and sharp teeth. These creatures, along with ferrets and minks, make up the Mustelinae subfamily.

Until now, researchers believed that the oldest fossils from this family were from Poland and Germany, dating back to about 3.5 million years ago in the . But a fossil discovered in Teruel, Spain, has doubled that estimate, dating back to the late , around 6.5 million years ago.

The research team, including , a �������� principal research scientist in the biology department, has identified this fossil as belonging to a new species, named Galanthis baskini. The researchers estimate that this creature was about 5 ounces, comparable in size to the smallest living carnivoran today, the or Mustela nivalis. Much like the modern weasel, G. baskini was also likely a carnivore, based on its teeth.

The team in Palaeontology.

“This study begins to uncover the evolutionary history of modern weasels, specifically, why do they have unique small, elongated bodies compared to all other mammals?” said Law, who is also an affiliate curator at the UW Burke Museum of Natural History and Culture. “We had hypothesized that events during the mid- to late-Miocene — both the expansion of open habitats, such as grasslands, and the diversification of rodents — would have allowed weasels to evolve bodies that were small and flexible enough to chase rodent prey in small crevices underground. G. baskini is exciting because it confirms that weasels were present in the Late Miocene. And it’s pretty cool that G. baskini was the size of the least weasel — that means small weasels were already around more than 6 million years ago.”

To compare this fossil to other weasel family members, the researchers used a combination of classical comparative anatomy with advanced analytical techniques, such as micro-computed tomography, or micro-CT. Micro-CT allowed the team to three-dimensionally reconstruct the internal structure of teeth and jaws as well as observe anatomical features that were not externally visible.

“The new genus, Galanthis, is named after a figure from Greek mythology who was transformed into a weasel, symbolizing the fossil’s significance as representing the origin of the weasel family and the lineage leading to modern species,” said senior author , assistant professor of paleontology at Complutense University of Madrid.

The fossils come from excavations carried out in the 1990s in the Teruel area of Aragón, Spain.

“This research is a clear example of the remarkable richness of Aragón’s fossil record of mammals, recognized worldwide,” said co-author , professor at the University of Zaragoza. “Our team has been contributing for decades to excavations and the study of fossil mammals.”

The study also revises the classification of another fossil of a similar age discovered in China. This fossil has now been assigned to the genus Zdanskyictis.

The next step, the researchers said, will be to find new fossils that help reconstruct in greater detail the early evolution of weasels and their relatives.

“Ideally, we will find an entire skeleton of a fossil weasel,” Law said. “That way we can actually quantify just how elongate these ancient weasels were and when body elongation actually evolved.”

A full list of co-authors and funding .

For more information, contact Law at cjlaw@uw.edu.��

Adapted from a release from Complutense University of Madrid.