UNH Magazine Winter 02

Photo by
Philippe Merle

In this issue:

Meet the Beetles
Dealing With Stress
Iron Man to the Rescue

Meet the Beetles

What's a dead mouse worth? Not much to you, no doubt, but in the natural world every small carcass is a treasure. Scavenging mammals and birds, a host of insects and even microbes and fungi want to claim it. The competition is intense.

According to UNH professor of zoology Michelle Scott, that stiff competition (please pardon the pun) explains why burying beetles do what they do. Commonly found throughout the northern hemisphere, these shiny black-and-orange insects are extremely sensitive to the odors of decomposition, so they are often the first creatures on the scene after an animal dies. The beetles can't defend their find from all of the competition, so they have to hide it--fast.

Typically, one male and one female beetle join forces to bury the animal, quickly excavating a grave and maneuvering the carcass into it. If more than one beetle of the same sex turns up, there is usually a fight, with the bigger beetle driving off the smaller one. Occasionally, a male and female will allow additional beetles to help them bury a large carcass, like a chipmunk, which the pair would not be able to handle alone.

A buried carcass is, in effect, the beetles' trust fund for the next generation. "Once the carcass is buried about four inches below the surface, the beetles construct a brood chamber," Scott explains. "They mate as they're working on the chamber, and within two days the female lays 30 or more eggs in a side tunnel. Three or four days later, the eggs hatch and the larvae climb to the top of the carcass, where both parents will regurgitate food to them."

The larvae grow rapidly, increasing their weight tenfold each day, and are soon feeding on their own. "When the young are three or four days old, one parent, usually the male, leaves," Scott says. "By the time the young are eight or nine days old, they have polished off the carcass, leaving only the largest bones. The larvae disperse to pupate in the soil, and the female's work is done."

This degree of parental care is quite unusual in the insect world. With the exception of social insects like ants and bees, few invertebrates pay any attention to their young. Their general policy is to produce as many young as possible and hope that some will survive. Why are burying beetles different? It was to answer that question that Scott started studying them 17 years ago.

The key to the puzzle is that precious resource, the dead mouse. "Burying beetles are an exception because they must find an unpredictable but very valuable resource in order to reproduce," Scott says. "Probably an individual has only one or two chances to reproduce in a lifetime, so each opportunity is tremendously important." A beetle's best bet for passing on its genes, therefore, is to stick around and do everything it can to ensure the survival of the brood it has already produced.

--Jake Chapline

Dealing with Stress

Victoria Banyard studies how people survive the horrific, how they rebuild their lives after experiencing the unthinkable. Banyard's research on extreme traumatic stress is encouraging, revealing that people heal, and there are many ways to recover from traumatic events, even extreme ones.

Stress has differing effects on people, says Banyard, associate professor of psychology at UNH, whose 10-year research focuses on the factors that allow individuals to deal with traumatic events. "Overwhelming stresses are disruptive for varying periods of time, and differing contexts can set up constraints or open up opportunities," she says. "I am most interested in people's strengths: what resilient people do and what survivors can teach us." Banyard wants to know why some people cope better and heal faster than others.

Banyard's research concentrates on subjects at the extreme end of the stress continuum, the homeless and victims of family violence. But her findings have implications for those dealing with more common sources of stress.

Banyard finds that those who recover quickly from stress choose positive coping strategies. While there are many paths to healing, she says, individuals who overcome traumatic events have similar responses.

Strengthening spiritual bonds and seeking professional help are common strategies, but less obvious activities are also curative: keeping a journal, exercising, seeking more information about the problem or getting lost in a hobby. Strategies work best in combination and some--drinking, smoking, taking drugs or "locking yourself away and pretending it didn't happen"--can be counterproductive. Several responses, such as turning to family and friends for support or helping others through the crisis, contribute to a more successful recovery. Being believed--yes, this terrible thing did happen to you--is particularly important, especially for children.

Choosing a coping strategy might appear to be a laborious process, but the choice is often made by default. Many people simply resort to what has worked in the past. The choices learned in childhood, says Banyard, are the ones people tend to make again. Using self-assessment and the feedback of others, adults are usually able to self-correct and pick healthier, more beneficial ways of coping. "After a tragedy, people can expect to feel off-balance, but most of us have a sense of how we are doing," Banyard says.

Some people get stuck, repeating similar responses even if they aren't working. "If the ones we love seem to be making bad choices," says Banyard, "we can talk to them, get help from friends and family, but ultimately the decision to change must be theirs."

Sometimes we don't have to think about what to do. Candlelight vigils, memorial services and active community involvement, tragically commonplace after Sept. 11, all help survivors to heal. In fact, Banyard is often amazed at how well people cope with tragedy. "I can't help but be struck by the strength of the human spirit, the resilience of people and their ability to overcome the odds," she says.

--Katy Kramer

Iron Man to the Rescue

If you've met UNH chemistry professor Dennis Chasteen, you've probably been educated on a topic that few Americans know about: the hazards of ingesting too much iron. This is a widespread health problem, and if people were aware of it they could do something about it, so Chasteen seizes any opportunity to spread the word. At Halloween he sometimes underscores his message by delivering a lecture in his Iron Man costume.

Chasteen's research focuses on transferrin and ferritin, two proteins that transfer and store iron in the human body. Although iron is essential for respiration and oxygen transport, too much can wreak havoc. Excess iron triggers chemical reactions that create highly reactive free radicals, which can damage the DNA, protein and lipids of cells and organs. "It is ferritin's role to compartmentalize and safely store iron in a nontoxic form, so it is available for making red blood cells," Chasteen explains, "but if we get too much iron, that mechanism begins to break down."

The people most affected by excess iron have a genetic disorder called iron-overload disease, or hemochromatosis. An estimated 1.5 million Americans suffer from the disease, although many don't know that they have it. Their bodies absorb too much iron each day--up to three times the normal amount. To lower their iron levels and prevent severe organ damage, they must have blood drawn regularly.

Chasteen's basic research on the movement of iron in and out of transferrin and ferritin may ultimately help in the development of new chelation treatments. Present chelation therapies allow excess iron to be excreted in the urine, but the medication can cost $25,000 a year.

Chasteen's work has been funded with approximately $6.2 million in grants from the National Institutes of Health over the past 29 years. He serves as a consultant to the government and other researchers striving to develop noninvasive ways to measure iron levels in patients with hemochromatosis and other iron-overload diseases. "Today the gold standard is a liver biopsy," he explains. "A lot of patients who go through this once say, 'You aren't touching me again!'"

People with hemochromatosis aren't the only ones who need to be concerned about too much iron. "For half the population--the male half--too much iron is not a good thing," Chasteen says, pointing to recent research linking higher iron levels to cancer, premature aging and an elevated risk of heart attack in normal people. "A certain amount of iron is essential, but if you go even a little beyond the optimal level, you're already on the down side."

By restricting red meat and iron-fortified foods in his own diet and avoiding multivitamins with iron, Chasteen strives to keep the iron in his blood at a level that would be typical for a premenopausal woman. A person ordinarily loses only about one milligram of iron a day (menstruating women being an exception). Thus, on a typical American diet, men and postmenopausal women steadily accumulate iron throughout their lives.

"In the past, the emphasis has been on iron deficiency, with little attention paid to the important problem of iron excess," Chasteen observes. In his Iron Man persona, he is trying to correct that oversight. As more and more evidence mounts, he's confident that his message will eventually become common knowledge. ~