Mary Poss: "It takes some time for an equilibrium to be established, We see this transition time as disease."

In 1900 the big news was that human speech could be transmitted through radio waves. It would be twenty-seven years before Alexander Fleming would discover penicillin, thirty-two years before Vitamin D would be identified, forty-two years before the most basic computer was developed. The country had found a new energy source to replace steam and the twentieth century was being heralded as “the age of electricity.” A sign of the staggering number of discoveries and technological achievements of the following one hundred years is that the age of electricity made possible by Edison’s invention of the light bulb is ending with global networking via the electronic computer chip.

Today several UM researchers are seeking answers to global problems we face as a people. Who would hazard a guess today what discoveries the next turn of a century will bring?

Back to HIV Basics

Even though the world’s population recently reached six billion, Worldwatch Institute statistics show HIV is measurably slowing population growth in certain areas. Nowhere is this more evident than in sub-Saharan Africa, a region of 800 million people, where AIDS is spiraling out of control. Researchers say that if a low-cost cure is not found soon, countries with infection rates of more than 20 percent, such as Botswana, South Africa and Zimbabwe, will lose one-fifth of their adult population within the next decade.

Despite all that has been learned about the human immunodeficiency virus, not much is known about the biology of the virus in human hosts, especially in women.

William Prentiss: "Smaller cultures are disappearing at an alarming rate."

In her small lab overflowing with students and glassware, Mary Poss, a UM assistant professor of biological sciences, is at work on the natural history of HIV, in particular the type belonging to clade A, the predominant form of the virus in Africa, where more than 60 percent of the world’s AIDS cases occur.

Typically, Poss says, retroviruses such as HIV cause no disease or only a slowly progressive, chronic disease in their hosts. Scientists suspect AIDS develops because HIV is relatively new in humans.

Poss is trying to determine how HIV adapts to new hosts and how it mutates within a population. She is particularly interested in the biology of the virus in its early stages and if the form transmitted through sexual contact is the same virus that later is detected in blood samples.

It appears that men are infected initially by a single form of virus, which replicates rapidly. In doing so, the virus makes mistakes, and soon there is a mixture of similar but slightly different viral forms in the host. When that individual infects another male, Poss says, “the clock is reset as far as diversity goes,” with only one form present at the new infection.

In women, however, the infection begins with quite a diverse population of viral forms. “We don’t know whether this diversity is a good or bad thing from a disease or therapy point of view,” Poss says. “It might be good because it helps maintain a broad immune response to keep the virus in check overall. Or maybe not.”

Using blood and cervical samples from infected women who regularly visited clinics in Kenya over a two-year period, Poss has been able to follow the evolution of a particular viral surface protein, GP120, and note how it has changed over time. GP120 is a key protein to watch, she says, because it interacts with cells to allow the virus to enter. It also is what the body recognizes and mounts an immune response to.

Her question is: Do genetic changes in the protein translate into different viral biologies in the host? Her studies suggest that HIV evolves differently when just one form is introduced than when a group of related viral forms is introduced at the same time.

If a highly pathogenic form of the virus doesn’t grow because of competition with other, less virulent, forms, you don’t want to decrease this competition through drugs; the virulent form could erupt. A better understanding of HIV biology at the time of transmission will increase the chances of developing an effective therapy. (CLK)

The Rise and Fall of Cultures

On a chilly late-spring afternoon, students in a UM archeology field course carefully dig narrow trenches in the ground and sift precise scoopfuls of dirt through screens hung from small tepee-like frames. Centimeter by centimeter their excavations reveal, in reverse time sequence, first the floor of a large shallow pit once covered by a roof of timber and woven grasses. This sheltered perhaps fifty people in several family groups about a thousand years ago. A bit lower down and intersecting the overbuilt floor lies a section of wall and floor of much older construction. Finally, deeper still, the students find hints of another floor built possibly three thousand years ago-an early example of habitation by people in transition from life as nomadic foragers to sedentary villagers practicing a “collector” lifestyle.

What causes some cultures to flourish in a particular time and place and others to disappear? What can societies today learn from the experiences of people who came before? Anthropologists and archeologists seek answers to these questions as they sift for clues left in the earth and in folk traditions that persist even though the conditions that gave rise to them are long gone.

In the Fraser River Canyon near Lillooet, British Columbia, UM archeologist William Prentiss is chronicling the lifestyles and adaptations of the native people of North America.

The Keatley Creek dig.

Last summer, Prentiss moved his family, eleven undergraduates and two graduate assistants to a camp along the canyon’s Keatley Creek for a six-week field study. The site contains 120 circular pithouses of varying sizes documenting “in an almost unparalleled state of preservation--the whole transition from forager to collector society to the abandonment of the large pithouse villages in the region after 1000 A.D.” he says. Keatley Creek represents “an amazing record of occupation,” where the place someone once sat to make a stone implement still can be seen.

According to Prentiss, humans have occupied the Fraser River Canyon for at least ten thousand years. They were descendants of hardy people who crossed the Bering Land Bridge from Siberia during the last Ice Age and filtered down the North American coast to Mexico.

“At first these were highly mobile people who foraged for food on a daily basis,” Prentiss says. “But sometime around five thousand years ago, we begin to see evidence of an increase in experimentation with the way things were done. There is evidence of mass collecting or harvesting of different foods depending on the season, then mass processing and storage.”

Prentiss thinks this was the situation four thousand years ago, when temperatures once again dipped significantly. Groups who still were dependent on foraging could not support the big populations that had arisen under good conditions. “If you weren’t storing it up, you were going to lose,” Prentiss says, while the groups who were using a collector approach to getting and storing food were able to cope.

“In biology there is the concept of diversification followed by decimation,” he says. This is an example of cultural diversification under generally good conditions followed by decimation when conditions changed. The same thing is happening globally today, though for different reasons.” (CLK)

A World With a View

The natural resource manager of the future will be able to monitor the health of vast tracts of wilderness with a few clicks of his or her mouse, thanks to UM’s Earth Observing System Training Center and NASA.

The EOS Training Center is an offshoot of the University’s work with NASA to create software that allows a fleet of satellites to observe and report natural conditions on our planet. The School of Forestry began working with NASA eight years ago, when forestry Professor Steve Running headed up a team that created software for NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS).

Lloyd Queen: "We've seen generations of progress in half a generation."

Scheduled to go up in NASA’s Terra satellite at press time, MODIS, a key instrument for monitoring global warming, will calculate global photosynthesis and evapotranspiration from earth’s plant cover to estimate deforestation, the likelihood of forest fires, pollution damage, crop conditions, glacial retreat and other conditions.

Running and researchers like forestry Associate Professor Lloyd Queen develop software tools that translate satellite data into information that natural resource and wildfire managers can use. Through the Natural Resource Project at the EOS Training Center, managers can learn how to download and use data from the Landsat-7 satellite.

Queen explains his latest research in terms a little closer to earth. Pictures taken from an airplane can tell us some things about the health of a forest below-the colors of the forest canopy are a good indication of its health and susceptibility to fire. But pictures taken from thousands of miles farther up can tell scientists even more.

“We’ve jumped into the next generation of forest and fire management,” Queen says. His research involves using digitalized information taken from energy wavelengths to monitor forest health and to make predictions about forest fires. He works in partnership with NASA, the U.S. Forest Service and the Bureau of Land Management.

“UM is perfectly located for this kind of work because we’re home to the International Fire Management Lab and close to several national forests,” he says.

The information taken from infrared wavelengths tells Queen how hot a fire is burning, what its combustion efficiency is, and whether the fire is smoldering on the ground or going up into the forest crown. In areas of the world with vast tracts of wilderness, remote sensing can help locate fires and determine their direction and intensity.

“There are two immediate applications for fire managers,” Queen says. “One is that through remote sensing we can and do monitor smoke plumes from fires. Not only does this tell us a lot about the fire itself, but it’s important for airshed managers.

“The second application is monitoring a forest’s surface moisture index. People always think of the fire itself, but a host of conditions affect how a fire will burn, including weather, fuel conditions and moisture content in the forest. Here in the West, the ignition source is almost always lightning. There’s nothing we can do about that. But we can survey the fuel and predict the outcome of an ignition.”

Dead fuels are difficult to sense, even remotely, because of their lack of chlorophyll which reflects light, but they can be detected using new laser technology-LIDAR. UM’s EOS program is the first in the Northwest to make use of LIDAR technology.

Using the NASA satellites, UM has been mapping the thermal characteristics of forest canopy for eleven western states every eight days for the past three years. The information is made available to forest managers online through UM’s Natural Resource Project.

“I am definitely entranced by the technology,” Queen says. “I love using this technology to give us more sophisticated, useful answers to questions we’ve always had.” (KA)

Alien Invaders

Alien invaders are sweeping the earth and it appears there is no stopping them. The introduction, intentionally or by accident, of alien plant and animal species is causing unprecedented changes--often irreversible damage--to ecosystems around the world.

The United States alone has become home to more than 6,000 exotic--that is, non-native--species, with dozens more arriving each year. Some of these, such as corn, wheat, cattle and poultry, are beneficial and have come to represent the lion’s share of the U.S. agricultural economy. Many others, however--from toxic leafy spurge to the marshland destroying nutria--choke out native species and threaten whole environments at an estimated annual cost of $138 billion. That figure does not even consider the biological cost inherent in the loss of species diversity. Ecologists say that such biological pollution poses nearly as great an environmental threat as habitat losses caused by development, clear-cut logging, overgrazing, mining and industrial accidents.

Because alien species usually do not dominate their native ecosystems, scientists and land managers not surprisingly have turned to alien predators, parasites and pathogens as a means of keeping invaders in check. In some cases such biocontrol efforts were successful. In others, biological agents have turned traitor and attacked native species or have caused unforseen ripples in the local food web. In still other situations, introduced biocontrols may have subtle and indirect effects on the health of native species, as UM biologist Ray Callaway is discovering.

One of Callaway’s research projects is studying knapweed and its interactions with other plants in a community. Knapweed is a native of central Europe and one of the most economically destructive invasive plants in the northwestern United States and southwestern Canada. In a few years knapweed can completely overrun acres of productive rangeland, out-competing the far more nutritious native bunchgrasses and turning the landscape into a sea of dead brown twigs in the fall.

Field and greenhouse experiments using different types of natural insect predators have shown that under average attack knapweed just grows better. Moreover, nearby grasses actually fare worse when knapweed is being preyed on than when it isn’t, especially when a certain type of soil fungi is present.

Another set of experiments compared the effects of U.S. knapweed and knapweed from the Republic of Georgia on related species of bunchgrasses from both the United States and Georgia; results showed that the Georgian grasses grew much better in the presence of knapweed than their American cousins. However, when certain compounds were added to the soil to mop up potentially harmful chemicals being exuded by knapweed roots, the American grasses grew only marginally better; the Georgian grasses grew much more poorly.

Ray Callaway: "We've played God with aquatic ecosystems... Now we're doing it with terrestrial systems and we need to be very careful."

“This was a very odd result,” Callaway says. “We would expect both grasses to benefit or for the American grasses to benefit a lot and the Georgian grasses to stay the same.”

A possible answer may be that Georgian grasses and knapweed evolved in the same communities and have a much more complicated relationship than current plant competition theory generally allows.

“I think we have underestimated the amount of co-evolution going on within plant communities,” Callaway says. And this has implications for the long-term efficacy of biocontrols, at least on plants. (CLK)

Elusive No More

How can you study and protect a species so elusive no one is sure how many there are or where?

PHOTO BY MILO BURCHAM

Scott Mills, an associate professor in the forestry school’s Wildlife Biology Program, gives a big smile. “Think of the O.J. Simpson trial,” he says. “Same technology.”

Through DNA profiling, scientists can identify the species that are found in a particular environment. They can identify individuals within a species and establish population sizes for species never before studied. For the first time, scientists also can make historical comparisons.

“We can take hair samples from museums and compare the genetic diversity found within a species a hundred years ago with genetic variations now. If we find that genetic variation has decreased, that’s an indicator of population isolation,” Mills explains.

DNA analysis allows scientists to study animals in the wild without having to go through the difficult and time-intensive process of capturing and marking them. Samples of feces or even a single hair taken from strategically placed rub pads can be collected. From these samples DNA profiles can be created.

“My concerns about how wildlife is doing as humans encroach on their environment is what led me to applied biology,” Mills says. “I have always wanted to learn what makes populations grow and decline.”

Scott Mills: "DNA technology is incredibly important, and I embrace it. But I tell my students not to be dazzled by it."

In a new three-year program in cooperation with the U.S. Forest Service, Mills and his research assistants will analyze all of the animal DNA samples taken from U.S. national forests. The project will be especially valuable in studying species like the Canadian lynx, which is so elusive and rare that it rarely has been captured and marked for study.

“We’ll work with the Forest Service to obtain hair samples from across the U.S.-every national forest from Maine to California. This technology enables us to identify which animals are found where and to undertake a capture-and-mark study where the animal is never touched,” he says.

While Mills is excited about the potential of DNA identification, he cautions students not to get obsessed with new technologies.

“Being out there in the environment is what being a biologist is all about, and there’s never a replacement for that immediate experience,” he says.

Besides his DNA work in the lab, Mills also heads several field projects in the Pacific Northwest to study the effects of forest fragmentation on wildlife species. A new four-year grant from the National Science Foundation supports “an army of undergraduate field assistants” who capture, mark and radio-track snowshoe hares in western Montana to learn about dispersal and birth and death rates in a variety of forest types. While Mills is obviously enthusiastic about what new high-tech tools allow him to do, it’s the big question that continues to fascinate him: What happens to animal populations when humans alter their environments? (KA)

Caroline Lupfer Kurtz is a frequent contributor to the Montanan and the University’s Research View newsletter. A Missoula-based freelance writer, Kim Anderson administers the Missoula Writing Collaborative.