In this issue:Tail Count
Much of science is the study of change over time. But you can't study how and why something has changed unless you know how it used to be—i.e., a baseline. In field biology, where change happens over large areas and many years, getting a baseline is often hard.
Rebecca Rowe, a new assistant professor of natural resources and the environment at UNH this fall, has tackled that problem in an interesting way—you might say she's channeling graduate students from the Jazz Age.
"In the 1920s, it was very popular to do your master's or doctoral thesis on 'The Mammals of X Place,'" she says. At the University of Utah, Rowe discovered treasure troves of field notes, trapping records, weights and measures, photographs and drawers full of preserved skins. For several years she and colleagues duplicated field work done by graduate students in 1927-29 in the Ruby Mountains of northeast Nevada to see what is similar and what is different.
The goal is to see how populations of small mammals like shrews and chipmunks have changed in eight decades. Small mammals are useful to study because of their numbers (there are lots of them) and their ecological niches, which are varied. "They can be very good signals of underlying changes in environmental conditions," says Rowe.
The results, published in the journal Global Change Biology, show that changes in the landscape caused by grazing cattle and sheep and the suppression of natural fires have compounded the impact of rising temperatures. Specifically, many desert dwellers aren't moving up into higher elevations even though temperatures there have warmed, as predicted by many large-scale models, because that habitat has changed and is no longer suitable. "Failure to account for land-use induced changes may provide misleading objectives for conservation policies," the paper warns.
A second paper, published in the journal Ecology this year, calculates the total number and types of small mammals and finds a distressing decline of roughly 50 percent over the 80 years. The missing total weight of small mammals—their biomass, in biologists' terminology—may have been replaced by more birds, reptiles or larger mammals, but it may also reflect a real decline in total productivity in the entire Great Basin region, which would be "a resource crisis," she writes.
Rowe hopes to apply the process of replicating old field research in New Hampshire. A number of surveys were done in the 1930s in the White Mountains, she says, so historical records should be available. A similar study here might lead to better understanding and management of animals and habitats today and in the future.
For a half-dozen years, UNH has been the scene of what might be considered a big experiment, designed to see how best to reduce sexual violence by convincing bystanders that it's OK to interfere. The experiment has provided a new way to tackle the hidden problems of sexual assault, relationship violence and stalking, using the power of peer pressure. "Nobody was using social marketing to address how bystanders can reduce the problem of sexual violence," says Sharyn Potter, associate professor of sociology.
Potter and colleague Jane Stapleton are trying to solve that problem through a bystander social-marketing campaign called "Know Your Power." Campaign images, which feature real UNH students, show young people discussing when to intervene to stop everything from date rape to public humiliation. The scenarios pull no punches, such as one where a young woman tells a friend, "I didn't want to have sex, but he forced me." They also address modern forms of harassment, such as an angry student posting explicit photos of his ex-girlfriend online.
The object is to break down barriers that keep people, particularly men, from intervening in their friends' affairs even when they secretly disapprove. If the posters, website and other marketing materials can convince students that their peers think it is sometimes appropriate to give advice, scold or even call police, perhaps they will take action.
The key to being convincing is to establish what Potter calls "social self-identification," which requires the scenarios to look real. To do that the researchers have used years of interviews, focus groups and surveys to get the little things right. "If the target audience members think, 'Oh, I would never wear a shirt like that,' then our research indicates they are likely to overlook the message," says Potter.
This process of refinement has led to publication in journals and adoption of the program at UMass-Lowell, the University of California system and the Army, although some details had to change. When developing posters for the military, for example, Potter notes, "one of the first things they said was, 'There's too much hair.'"
UNH has employed Know Your Power and the "Bringing in the Bystander" in-person prevention program developed by professors Victoria Banyard and Mary Moynihan as part of its long effort to combat sexual violence, as well as its Sexual Harassment and Rape Prevention Program. The researchers have conducted many surveys of students to judge effectiveness and have found statistically significant changes in attitudes. The next step is to see if the numbers of actual sexual assaults are dropping, but that measurement is complicated by the fact that public awareness makes people more likely to report incidents. Still, with some studies estimating that nationally, as many as one in five people are victims of some sort of sexual assault during their college years, Potter is pursuing this goal, too.
It doesn't take a rocket scientist to know that getting bombarded with galactic cosmic rays is probably not a good thing for you. But it turns out these high-energy particles zipping hither and yon in the far reaches of the Milky Way have likely played a positive role in the long-term evolution of life on Earth by introducing random zaps of gene mutations.
Moreover, it has been postulated that cosmic rays penetrating Earth's various protective shields eventually interact with our atmosphere and play a role in the planet's climatic conditions, which seesaw hot and cold through the millennia and are, of course, a current source of concern.
Making the connection between Earth's climate and galactic cosmic rays is more art than science at the moment because much of the underlying physics remains fuzzy. It's also exceedingly difficult to make the requisite measurements. But scientists, including those at UNH, are getting closer to piecing together a variety of puzzle parts that may eventually provide better understanding of conditions favorable to life as we know it throughout the cosmos.
One important piece in the puzzle was recently acquired by NASA's bus-wheel-sized IBEX spacecraft, short for Interstellar Boundary Explorer spacecraft, which has been probing the edges of our solar system since 2008.
The mission is creating the very first maps of the boundary between our solar system and interstellar space by means of highly specialized cameras built in part at the Space Science Center in UNH's Institute for the Study of Earth, Oceans, and Space.
The cameras create images by capturing energetic neutral atoms that come close to the Earth from the edge of the solar system. The images are etching the first glimpse of the huge, magnetic bubble that envelopes the sun—the heliosphere, which serves as the initial layer of protection against cosmic rays. Or so it was thought, before IBEX's most recent discovery.
The latest series of maps derived from IBEX imagery revealed a mysterious ribbon of energy "painted" across a vast region of the heliosphere. The discovery shows that the interstellar magnetic field (as denoted by the ribbon) surrounding our solar system is a critical component in the structure of the heliosphere, and in effect may provide an additional layer of protection from the rays. The discovery overturns 40 years of theoretical space physics, which has operated on the assumption that the heliosphere's shape and structure are primarily controlled by interstellar gas and plasma and the sun's motion through it. The finding has major implications for advancing the frontiers of heliospheric physics.
"Until this discovery, we had only a vague idea about the strength of that interstellar magnetic field or its direction," says physics professor Eberhard Moebius, UNH's principal investigator for the IBEX mission. "With respect to protecting against cosmic rays, ultimately magnetic fields are the key, and we now realize we have the interstellar magnetic field draped around the heliosphere, giving us two layers of shielding."
All of which is meaningful for understanding the magnetic shielding needed to incubate life—that evolution-driving "sweet spot" of not too much and not too little.
"Our whole solar system can be thought of as a case study for the emergence of life," notes Nathan Schwadron, an associate professor of physics and an IBEX mission scientist. "So fully understanding the dynamics of our own neighborhood is a keystone for unraveling the mystery of habitability within the cosmos."
For a video, see www.unh.edu/ucm/animations/physics
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