“It felt like something out of the Lord of the Rings — like Mordor. It was hard to imagine much surviving,” said Justin Brashares, a professor of environmental science, policy and management at the University of California, Berkeley.

But mere months after the fire, animals like coyote, gray foxes and black-tailed jackrabbits were seen returning to the area, spotted by grid of motion-sensor camera traps that Brashares’ lab has operated since 2016 at the HREC, a multidisciplinary research and education facility located on the banks of the Russian River about and 13 miles south of Ukiah.

“We were surprised that many species seem to be resistant [to the impacts of the fire],” said Kendall Calhoun, a graduate student at UC Berkeley and a member of Brashares’ lab.

Calhoun is the lead author of a new study that analyzed more that 500,000 camera grid images taken at the HREC in the years before and after the Mendocino Complex Fire to understand how the blaze impacted small- and medium-sized mammals on the property.

The study, which appeared Monday in the journal Ecosphere, is one of the first studies to compare continuous wildlife observations made before and after a megafire. It is also one of a limited number of studies to focus on the impacts of megafires on California’s oak woodlands. Oak woodland ecosystems comprise a large portion of the state, and yet are underrepresented in wildfire research compared to the conifer forests of the Sierra Nevada.

“For the great majority of Californians, these oak woodlands and grassland savannahs are what we think of as the characteristic biome or ecosystem type for our state,” Brashares said. “It’s the primary ecosystem type for livestock grazing, and it’s also the primary habitat type that’s used to grow grapes for wine. It’s a critical ecosystem type, and it’s worth managing well.”

Of the eight animal species included in the study, six were found to be “resistant” to the impacts of the fire, using the area in the same ways and with approximately the same frequency as they did before the fire. These species included coyote, black-tailed jackrabbit, gray fox, racoon, striped skunk and bobcat. Western gray squirrel and black-tailed deer, however, appeared to be more vulnerable to the impacts of the fire.

Brashares and Calhoun believe many of the species were able to remain in the area thanks to small patches of tree cover spared by the fire. Photos from the camera traps reveal many animals taking refuge in these patches, using them to obtain food and resources while more heavily burned areas recovered. Some animals were even observed using these locations more often after the fire than before.

These findings highlight the importance of using techniques like grazing and prescribed burning to reduce the intensity of wildfires when they happen. These lower severity fires are more likely to leave the tree canopy intact and create the types of forest heterogeneity that can benefit fire-adapted ecosystems.

“Even this incredibly hot and devastating fire still managed to leave behind these little patches of unburnt areas, andwe were surprised at how quickly many species were able to move into those habitat patches and then spread back out into the burned areas as they recovered,” Brashares said. “This finding is very valuable for forest management because we can do things to the landscape that will increase the chance that when fire does come through, it will leave behind some of these fragments.”

An approaching inferno

Calhoun was halfway around the world visiting New Zealand when he received a text message from study co-author Kaitlyn Gaynor informing him that the HREC was on fire.

“I think my immediate text back was, ‘Is everyone okay?'” Calhoun said.

For two years, Calhoun had been helping to maintain the 36 camera traps spread across the property that had been set up in collaboration with the California Department of Fish and Wildlife to test a new way to monitor wildlife populations across the state.

Calhoun had originally joined Brashares’ lab hoping to study impacts of megafire on wildlife diversity, but the unpredictability of wildfire had made it difficult to find a study site. The Mendocino Complex Fire — while terrifying and destructive — provided him with a rare opportunity.

“From what I heard, it was really scary as the fire was coming up to the property because people live on site, so there was a big rush to evacuate. The fire ended up burning more than half of the area,” Calhoun said. “I was a continent away when I found out, but I was interested in hitting the ground running and making sure we got all the data we needed when I got back.”

Calhoun and the team first returned to the site about two months after the fire, when trees were still smoldering and the HREC resembled a “moonscape.” The team’s first task was to check on the cameras, 13 of which had been partially melted by the fire. In addition to replacing broken camera parts, they also checked to make sure the camera traps were set up at the same position and with the same orientation as they were before the fire, to ensure that their data remained as consistent as possible.

Every three months, the team visits all 36 cameras on the site, downloading the photos, ensuring that everything is working correctly and removing any grass or debris blocking the view. They then spend countless hours reviewing each shot to sort out which photos contain animals, then identify the animals and log the data.

“A lot of the data that we collect is just grass blowing in the wind,” Calhoun said.

In addition to small- and medium-sized mammals, the cameras also capture photos of larger animals, like black bears and mountain lions. Because these apex predators have huge home ranges — often many times larger than the HREC’s 5,300 acres — it is impossible to get accurate information about their distributions from the study area.

Calhoun said that, anecdotally, these animals were spotted much less frequently after the fire, suggesting that they were slower to return to the area after the blaze.

After completing his Ph.D. this summer, Calhoun plans to continue his work as a 2023 Smith Fellow, studying how broad changes in fire regimes are affecting wildlife species across California. As part of the work, he hopes to obtain broader scale data on apex predators to better understand what happens to these animals when large fires destroy their home ranges.

“For my next project, I’m really interested in looking at the broadscale effects of fire on those really wide-ranging species, like mountain lions and bears, and then also how wildfires might be impacting their relationship with people,” Calhoun said. “The conflict between bears and humans, especially in Lake Tahoe, is really big in the in the news right now, and I think that either climate change or fire might be driving some of those interactions.”

Additional study co-authors include Benjamin R. Goldstein, Kaitlyn Gaynor, Alex McInturff and Leonel Solorio of UC Berkeley. This work was supported in part by the California Department of Fish and Wildlife (CDFW Grant # P1680002) and by the NSF Graduate Research Fellowship program.

“Value isn’t just determined by an objective reward or outcome,” Collins said. “Our research suggests that people’s perception of value is largely shaped by their personal goals and the context in which the decision is made.”

For example, you might order a chocolate ice cream cone and be perfectly satisfied with your choice. But if you then find out that there’s another flavor available, you might feel less satisfied with your initial selection. In this case, the objective value of the ice cream cone hasn’t changed. What’s changed is your subjective perception of its value relative to the newfound best option, thus highlighting the impact of goal achievement on decision-making.

Using data collected from over 1,000 individuals by various laboratories, the Berkeley team has confirmed this theory by developing an “intrinsically enhanced” reinforcement learning model. While other theories propose that subjective value is simply adjusted based on different observed alternatives, the model developed by Berkeley researchers offers a new perspective: it centers around the concept that achieving a goal is crucial. The intrinsically enhanced model is not the first to examine this phenomenon, but it does provide a new way to understand the problem.

“Our study proposes a paradigm shift in how we understand decision-making,” Molinaro said. “It shows the critical importance of considering goal-dependent rewards, which may significantly alter our understanding of decision-making processes.”

The potential applications of this research are vast and varied. This new understanding could inform public policies encouraging positive behavior changes or help shape financial decisions. In an educational setting, it could be utilized to show students how learning specific topics can assist in achieving their particular goals. The research could also inform therapeutic strategies for patients suffering from mental illness or eating disorders.

This research could inspire innovation in the field of the development of artificial intelligence. “As it stands, an AI model cares primarily about extrinsic rewards,” Collins said. “Our research suggests that integrating intrinsic, goal-oriented rewards could substantially enhance these models.”

While these findings are a significant step forward in understanding decision-making processes, further research is needed to fully understand and apply this concept across various fields. The Berkeley team plans to continue exploring this important area of cognitive neuroscience.

Even jaguars poop.

A team of researchers led by the University of Cincinnati applied genetic and isotopic analyses to jaguar scat to investigate the habitat needs of the big cats in the Mountain Pine Ridge Forest Preserve of Belize in Central America. The study demonstrates a novel and noninvasive technique for identifying the landscape use and conservation needs of elusive wildlife.

Researchers used scat-detecting dogs named Billy and Bruiser to find telltale evidence left behind by jaguars in the reserve, which is also home to pumas, margays, ocelots and jaguarundis. They subjected the scat to genetic analysis, known as molecular scatology, to identify not just species but also the individual cats that produced each sample. Researchers then subjected the scat to isotopic analysis, which offers clues about where the animal hunted based on the geology and vegetation of the area.

Published in the European Journal of Wildlife Research, the study concluded that the combination of genetic and isotopic analysis provides a powerful, noninvasive approach to surveying wildlife for conservation.

“We’re not interacting with the animal directly,” said Brooke Crowley, lead author and a professor of geosciences and anthropology at the University of Cincinnati. “There’s no trapping or darting. You might never see the animal, but can determine what it ate and where it ate it.”

The Mountain Pine Ridge Forest Reserve covers about 267 square miles of forest, savanna, rocky mountains, caverns and streams in central Belize. The reserve is logged on a rotating basis. The roads are largely unpaved and many are overgrown.

Tracking animals here is extremely difficult, said Claudia Wultsch, a study co-author and research fellow at the City University of New York.

“Jaguars tend to stay away from people and are typically found at more remote sites. You have to be extremely lucky to see one in the wild,” Wultsch said.

Isotopic analysis is a good alternative to study an animal that is solitary, wide-ranging, nocturnal, wary of people and dangerous to capture. And it complements other wildlife surveillance methods such as camera trapping, acoustic monitoring and environmental DNA analysis.

Bigger than leopards, jaguars are the world’s third-largest cat and the biggest found in the Western Hemisphere. They are powerful apex predators that were revered by pre-Columbian societies. Opportunistic hunters, jaguars consume a wide variety of prey, including small mammals, birds, fish and reptiles. In Belize, they often eat armadillos, coatis and deer.

“Belize is an important stronghold for jaguars,” co-author Wultsch said. She is studying the big cats with study co-author Marcella Kelly, a professor at Virginia Tech.

In Belize, jaguars are protected and live in a network of dedicated reserves. Wultsch and Kelly in 2000 found that jaguars had a large enough population to maintain genetic diversity in Belize but did see some habitat loss and fragmentation in parts of their historic range.

In the latest project, the jaguars the researchers studied hunted prey in the reserve’s pine forest savanna rather than in denser forest or nearby agricultural areas. Male jaguars had territory covering some 60 square miles. As in other areas where jaguars have been studied, researchers found that some of the male jaguars had partially overlapping territories.

They also found some evidence that the jaguars were avoiding areas where prey was scarce from recent wildfires. This corroborates a camera trapping study that had fewer sightings of both jaguars and their prey in these areas as well.

“Some forested areas in Belize have become more fragmented and isolated over the last 50 years, so one of the objectives of our research is to assess how jaguars are doing at several protected areas across Belize,” Wultsch said.

The study was supported by grants from the Virginia Tech Department of Fish and Wildlife Conservation, the Explorers Club, the nonprofit group Panthera, the National Geographic Society, the Oregon Zoo, the Woodland Park Zoo, the Roger Williams Park Zoo and the Wildlife Conservation Society.

During his career, Franklin printed nearly 2,500,000 money notes for the American Colonies using what the researchers have identified as highly original techniques, as reported in a study published this week in the Proceedings of the National Academy of Sciences.

The research team, led by Khachatur Manukyan, an associate research professor in the Department of Physics and Astronomy, has spent the past seven years analyzing a trove of nearly 600 notes from the Colonial period, which is part of an extensive collection developed by the Hesburgh Libraries’ Rare Books and Special Collections. The Colonial notes span an 80-year period and include notes printed by Franklin’s network of printing shops and other printers, as well as a series of counterfeit notes.

Manukyan explained that the effort to print money for the fledgling Colonial monetary system was important to Franklin not just as a printer but as a statesman as well.

“Benjamin Franklin saw that the Colonies’ financial independence was necessary for their political independence. Most of the silver and gold coins brought to the British American colonies were rapidly drained away to pay for manufactured goods imported from abroad, leaving the Colonies without sufficient monetary supply to expand their economy,” Manukyan said.

However, one major problem stood in the way of efforts to print paper money: counterfeiting. When Franklin opened his printing house in 1728, paper money was a relatively new concept. Unlike gold and silver, paper money’s lack of intrinsic value meant it was constantly at risk of depreciating. There were no standardized bills in the Colonial period, leaving an opportunity for counterfeiters to pass off fake bills as real ones. In response, Franklin worked to embed a suite of security features that made his bills distinctive.

“To maintain the notes’ dependability, Franklin had to stay a step ahead of counterfeiters,” said Manukyan. “But the ledger where we know he recorded these printing decisions and methods has been lost to history. Using the techniques of physics, we have been able to restore, in part, some of what that record would have shown.”

Manukyan and his team employed cutting-edge spectroscopic and imaging instruments housed in the Nuclear Science Laboratory and four Notre Dame research core facilities: the Center for Environmental Science and Technology, the Integrated Imaging Facility, the Materials Characterization Facility and the Molecular Structure Facility. The tools enabled them to get a closer look than ever at the inks, paper and fibers that made Franklin’s bills distinctive and hard to replicate.

One of the most distinctive features they found was in Franklin’s pigments. Manukyan and his team determined the chemical elements used for each item in Notre Dame’s collection of Colonial notes. The counterfeits, they found, have distinctive high quantities of calcium and phosphorus, but these elements are found only in traces in the genuine bills.

Their analyses revealed that although Franklin used (and sold) “lamp black,” a pigment created by burning vegetable oils, for most printing, Franklin’s printed currency used a special black dye made from graphite found in rock. This pigment is also different from the “bone black” made from burned bone, which was favored both by counterfeiters and by those outside Franklin’s network of printing houses.

Another of Franklin’s innovations was in the paper itself. The invention of including tiny fibers in paper pulp — visible as pigmented squiggles within paper money — has often been credited to paper manufacturer Zenas Marshall Crane, who introduced this practice in 1844. But Manukyan and his team found evidence that Franklin was including colored silks in his paper much earlier.

The team also discovered that notes printed by Franklin’s network have a distinctive look due to the addition of a translucent material they identified as muscovite. The team determined that Franklin began adding muscovite to his papers and the size of this muscovite crystals in his paper increased over time. The team speculates that Franklin initially began adding muscovite to make the printed notes more durable but continued to add it when it proved to be a helpful deterrent to counterfeiters.

Manukyan said that it is unusual for a physics lab to work with rare and archival materials, and this posed special challenges.

“Few scientists are interested in working with materials like these. In some cases, these bills are one-of-a-kind. They must be handled with extreme care, and they cannot be damaged. Those are constraints that would turn many physicists off to a project like this,” he said.

But for him, the project is a testament to the value of interdisciplinary work.

“We were fortunate to have student researchers on this project with interests both in physics as well as in history and art conservation. And the core research facilities as well as the Rare Books and Special Collections team were incredible research partners. Without an uncommon level of collaboration across disciplines, our discoveries would not have been possible.”

How do these networks form and how are they maintained? For the long-lived macrophages (phagocytes), the answer is already known: They settle in so-called niches. These are environments of connective tissue cells that supply the macrophages with nutrients and keep them alive.

A team led by Professors Georg Gasteiger, Dominic Grün and Wolfgang Kastenmüller from the Institute of Systems Immunology at Julius-Maximilians-Universität Würzburg (JMU) / Max Planck Research Group has now turned its attention to a related type of immune cells, the so-called dendritic cells.

These immune cells are essential for the control of immune responses because they are at the first line of defense of the immune system: They recognize foreign structures, take them in and process them into a kind of mugshot. They then present the photo to other immune cells and trigger a specific immune response, for example against pathogens or cancer cells.

Dendritic cells migrate through the tissue

The special thing about dendritic cells: They only live for about a week and during this time they continuously migrate through the body’s tissues. “In this respect, it was clear that the classic niche concept would not work here” , says Wolfgang Kastenmüller.

The JMU team found a completely new concept for this, according to which three-dimensional cell networks can organize themselves: Dendritic cells orient themselves to the blood vessels and migrate one after the other along their outer wall – similar to children walking in single file. The blood vessels thus determine the three-dimensional arrangement of the cells.

Cytokines keep the cells together

“We wanted to understand how this process is regulated and how the cells manage to close gaps in their network,” explains Dr. Milas Ugur, a scientist in Professor Kastenmüller’s group. Closing such gaps is important because otherwise the immune defense no longer functions optimally.

As the JMU team reports in the journal Immunity, it is due to a locally acting cytokine, the FLT3 ligand, that the dendritic cells always stay close together during their developmental migration.

The cytokines are continuously and evenly produced locally and consumed by the dendritic cells. If there are gaps in the group, more cytokines are available for the isolated dendritic cells. This surplus speeds them up in their development and movement and helps them to reconnect with the group. When the cells have moved up, they have a little less cytokines available again due to competition from their neighbours. Accordingly, they slow down their developmental speed.

Of prognostic value for tumour diseases

These findings are for example important  for cancer therapy: dendritic cells have a high prognostic value for tumour diseases: The higher their abundance in the tumour, the better the prognosis for the patient. This is especially true after immunotherapy.

“Increasing our basic insights on dendritic cell biology will help us to restore the networks of these cells in tumours and thereby tailor optimal therapies in the future” explains Kastenmüller.

How the researchers are moving forward

The JMU researchers’ data so far is based on the analysis of lymph nodes from animal models. The team next wants to test whether the same principles of network organisation of dendritic cells apply to all tissues and also in humans.

The work described was done in cooperation with researchers from the Würzburg Helmholtz Institute for RNA-based Infection Research (HIRI) and with scientists from France and Japan.