The study, published in the May 2025 issue of The American Naturalist, found that the masked shrew (Sorex cinereus) reduces its body mass by 13 percent in the colder months; the creature then grows larger in spring when conditions improve. In addition to a shrinking body, the team also found seasonal changes in the height of the creature’s braincase (the portion of the skull that houses and protects the brain) and the length of the femur.

“Shrinking the body and its parts is in fact a clever survival strategy,” says McLean. “And it’s one that’s important for us to understand as mammals face a constantly changing planet.”

Known as Dehnel’s phenomenon, this seasonal shrinking has been observed in other mammals but most often in shrews, which are small, insect-eating animals unrelated to rodents. Dehnel’s phenomenon is an extreme example of “phenotypic plasticity” — the ability of an organism to alter its physical form in response to environmental changes.

“We don’t know how common Dehnel’s phenomenon is among mammals, but we know it is rarer in nature than other energy-saving strategies mammals use, like hibernation,” said McLean.

McLean and his team of graduate and undergraduate students analyzed 125 masked shews that were trapped in North Carolina’s Pisgah National Forest from 2021 to 2023. The team used “pitfall traps” buried in leaf litter to capture the shrews. The animals were weighed in the field, then brought to UNCG’s Joint School of Nanoscience and Nanotechnology for microCT scans to examine various skeletal dimensions. Specimens and associated data are archived in the UNCG Mammal Collection. Researchers from Georgia Southern University were also involved in the research.

“Our population of masked shrews is the southern-most yet studied for these multiple different traits,” said McLean, “and the femur measurements we made are the first to show the magnitude of seasonal change in the long bones of the skeleton. This shows that shrews rapidly remodel much of their skeleton.”

Most prior studies of the phenomenon come from Europe. To place their new results in context, the researchers also conducted a meta-analysis of 74 other studies from across the Northern Hemisphere, combining that research with their own findings to understand what factors drive Dehnel’s phenomenon. McLean and his team developed statistical models that accurately predicted the amount of body shrinkage they observed based solely on the climate at the North Carolina site.

“This analysis reveals the generality of Dehnel’s phenomenon in Sorex shrews,” explains McLean. “Across many populations of shrews on three continents, the degree of body mass and braincase height shrinkage is greatest in areas with the lowest cool-season temperatures. So, fall and winter temperatures predict Dehnel’s phenomenon in these animals.”

“Phenotypic plasticity is a key way that shrews and many other species respond to changes in temperature,” McLean notes. “By learning more about this process, we can start to understand how mammals buffer against rapidly changing climates.”

Ramirez-Marquez, associate professor and division director of Enterprise Science and Engineering at Stevens, who grew up in the earthquake-prone Mexico City knows this first-hand. “Whenever there’s an earthquake, a city-wide alarm goes off and everybody leaves wherever they are and stays in the middle of the street — that’s a prevention phase,” he says. “Then there’s a restoration phase when people engage with others in the community, whether it’s sharing food and water or helping rescue people from under the debris.” The community’s solidarity and togetherness — one for all and all for one, per a Latin proverb — are key to bouncing back.

In scientific terms, this togetherness is defined as community cohesion, which encapsulates the sense of belonging, mutual support among members and shared values or sentiments, all of which boost community’s ability to withstand disasters. But whether this cohesion directly influences how well a community recovers from extreme events is not known, explains Alexander Gilgur who had studied this subject with Ramirez-Marquez as a Ph.D. student. “Resilience is a measure of how quickly and/or effortlessly the system recovers from a disturbance,” says Gilgur. “The causal relationship between cohesion and resilience appears logical, but it has not been proven mathematically.”

To address that issue, Gilgur and Ramirez-Marquez developed mathematical techniques to measure community cohesion and its resilience, which they outlined in a recent paper, published in the journal of Socio-Economic Planning Sciences. They investigated two case studies of the same San Francisco Bay Area community during 2020 wildfires and during 2022-23 rainstorms.

In their work, they found that during the less intense adverse events such the rainstorms, the community performance improved despite the increasing stress levels. However, in high-stress disturbances such as the wildfires, the community’s performance suffered. “We found that there’s a negative correlation between the resilience of a community and the strength of disturbance,” says Ramirez-Marquez.

In fact, in some cases, the disturbance could be so strong that people may forsake their community. Ramirez-Marquez cites the recent Los Angeles fires example (which wasn’t part of the study, but is telling), where more affluent residents hired private firefighters to keep their houses safe. “So when the stress is very strong, some might say, ‘oh, well, I don’t care about the community, I care about myself.’ The stress can be so high that the concept of community cohesion no longer stands.”

The scientists also found that the emotion intensity has a strong effect on community cohesion. “For helping communities be more resilient, emotional engagement is a very important factor,” says Gulgur, adding that it doesn’t matter whether emotions are positive or negative. “Anger and fear are equally powerful as joy and love.” On the contrary, people’s economic level does not have a direct effect on the community cohesion, “because the disaster might affect everyone,” says Ramirez-Marquez.

He notes that developing metrics to assess community cohesiveness and resilience offers practical benefits. If we can establish the causal link between cohesiveness and resilience, we can then set thresholds, limits or targets — and use these metrics to implement policies that aim to reach the desired numbers to improve resilience.

“Community cohesiveness is essentially a social glue that holds people together,” Ramirez-Marquez says. Quantifying that glue is challenging, yet being able to do so can help indicate whether a given community is resilient or can be stronger. “These metrics can then be used by policymakers to implement policies that make communities more resilient.”

The consequences of heavy drinking — which is defined as four or more drinks per occasion for women and five or more for men — are felt throughout the college community. These include blackouts, academic underperformance and interpersonal problems. Then there are the secondhand consequences for students who don’t drink, such as interrupted study, aggression, assault and having to care for intoxicated peers.

In a new study, researchers from the Brown University School of Public Health developed and tested an intervention called Counter-Attitudinal Advocacy (CAA). CAA involves advocating for a position that contradicts a personally held attitude or behavior. In this context, CAA targets positive perceptions of heavy drinking and the belief that alcohol is an essential part of college life.

In randomized controlled trials at two sites with 585 college students, researchers compared CAA to the well-established Personalized Normative Feedback (PNF) to evaluate their effectiveness in decreasing drinks per week, peak blood alcohol concentration and alcohol-related consequences relative to a control group. Researchers focused on drinks per week, a standard measure given the irregular drinking patterns of college students, who often veer between heavy drinking and alcohol-free days.

Ultimately, they worked on answering two main questions:

• Does CAA effectively reduce alcohol-related risk compared to our control?
• How does CAA compare to PNF, which has proven to be an effective low-cost way of reducing alcohol consumption among high-risk students?

Here’s what they found: Participants who received PNF reported significantly fewer drinks per week than the control group, while those who received CAA reported significantly fewer consequences. CAA had a harm reduction effect on consequences — its intended focus — but not on consumption of alcohol, which it did not target.

“Both interventions take just 5-10 minutes, making them ideal for broad prevention efforts,” said Kate Carey, co-lead investigator of the study and professor of behavioral and social sciences at Brown. “Our results showed that PNF did reduce alcohol consumption, as expected. But CAA specifically reduced the number of problems participants reported due to drinking. So, while they had different effects, they were complementary — giving us another useful tool for harm reduction.”

Carey explained that PNFs show participants how their drinking habits stack up against those of their peers, often exposing a common misconception that others drink more than they actually do: an insight that can help them adjust their own behavior. In contrast, CAA encourages participants to reflect on why it is a good idea to avoid alcohol-related problems, such as passing out or taking excessive risks, and to identify specific actions they can take to minimize these risks.

“Instead of directly telling students what to do, we prompt them to generate their own strategies,” Carey said. “This makes the intervention personalized and non-confrontational. Unlike some interventions that make people feel defensive about their drinking, CAA frames the discussion more broadly: ‘Why is it good for young people to avoid problems?’ rather than ‘You personally need to change.'”

As participants responded to these prompts, a research assistant or peer asked them to explain their written responses. Carey noted that this act of verbal reinforcement likely strengthened the intervention’s effect, since we tend to feel more committed to our viewpoints when we share them publicly.

It’s important to have a variety of brief interventions, since no single approach works for everyone, Carey stressed. Offering multiple evidence-based options increases the chances of reaching more people who are undergoing a period of heightened risk.

The research team, which includes co-primary investigators Angelo DiBello associate professor of applied and professional psychology at Rutgers University and Clayton Neighbors, professor of social psychology at the University of Houston, are encouraged that CAA provides another effective tool — especially for those who may not respond to PNF.