Article courtesy of Biomarker Magazine from the University of Illinois Institute for Genomic Biology.

“Well, in our country,” said Alice, still panting a little, “you’d generally get to
somewhere else — if you run very fast for a long time, as we’ve been doing.”
“A slow sort of country!” said the Queen. “Now, here, you see, it takes all the running you can do, to keep in the same place. If you want to get somewhere else, you must run at least twice as fast as that!”
-Lewis Carroll, Through the Looking Glass

Inspired by the Red Queen in Lewis Carroll’s Through the Looking Glass, collaborators from the University of Illinois and National University of Singapore improved a 35-year-old ecology model to better understand how species evolve over decades to millions of years, as reported in Ecology Letters.

The new model, called a mean field model for competition, incorporates the “Red Queen
Effect,” an evolutionary hypothesis introduced by Lee Van Valen in the 1970s that suggests
organisms must constantly increase their fitness in order to compete with other ever-evolving organisms in an ever-changing environment. The mean field model assumes that new species have competitive advantages that allow them to multiply, but over time new species with even better competitive advantages will evolve and outcompete current species, like a conveyor belt constantly moving backwards.

The model gets its name from field theory, which describes how fields, or a value in space and time, interact with matter. A field is like a mark on a map indicating wind speeds at various locations to measure the wind’s velocity. In this ecological context, the “fields” approximate distributions of species abundances. Ecologists can use models to predict what happens next and diagnose sick ecosystems, said Assistant Professor of Plant Biology James O’Dwyer, who co-authored the study.

CREATING A MODEL ECOLOGY MODEL
The mean field model has improved a fundamental ecology model, called neutral
biodiversity theory, which was introduced by Stephen Hubbell in the 1970s. Neutral theory
does not account for competition between different species, thus considering all species to be selectively equal.

“The neutral model relies on random chance,” said O’Dwyer, who is a member of the Biocomplexity theme. “It’s like a series of coin flips and a species has to hit heads every time to become very abundant. That doesn’t happen very often.”

Neutral theory can predict static distributions and abundances of species reasonably well, but it breaks down when applied to changes in communities and species over time. For instance, the neutral model estimates that certain species of rainforest trees are older than Earth.

“At one end of the spectrum, we have this neutral model with very few parameters and very simple mechanisms and dynamics, but at the other end, we have models where we try to parameterize every detail,” O’Dwyer said. “What’s been hardest is to take one or
two steps down this spectrum from the neutral model without being sucked down to this very complicated end of the spectrum.”

By creating a more realistic model that incorporates species differences, O’Dwyer and co-author Ryan Chisholm, an assistant professor at National University of Singapore, have taken an important step down that spectrum. “Our model is not the ecological equivalent of Einstein’s General Theory of Relativity, which was a conceptual leap for physics,” O’Dwyer said. “It is an incremental step at this point. But we will need those conceptual leaps that incorporate the best parts of different models to really understand complex ecological systems better.”
The Templeton World Charity Foundation
supported O’Dwyer’s work.

You can view the complete Biomarker magazine here

University of Illinois professor of entomology May Berenbaum has been awarded the National Medal of Science, the nation’s highest honor for achievement and leadership in advancing the fields of science and technology, according to an announcement from the White House Press Office.Photo Courtesy National Science and Technology Medals Foundation

The National Medal of Science was created in 1959 and is awarded annually to individuals who have made outstanding contributions to science and engineering, according to the release.

“Professor Berenbaum’s work has fundamentally changed what we know, how we study and how the public understands the role of insects in nearly every aspect of human life and development,” said

Phyllis M. Wise, chancellor of the Urbana campus. “This is transformative scholarship on a global scale and has implications for every person on the planet. This is a well-deserved honor and all of us at Illinois offer Professor Berenbaum our sincerest congratulations.”

Berenbaum, a Swanlund Chair and the head of the department of entomology, has been a U. of I. faculty member since 1980. Her research, which studies the chemical mechanisms underlying interactions between insects and their host plants, including the detoxification of natural and synthetic chemicals, has produced hundreds of peer-reviewed scientific publications and 35 book chapters.

She also created the Insect Fear Film Festival, now in its 32nd year on campus. The festival engages and entertains hundreds of viewers each year with feature-length films and shorts, commentary on the films, an insect petting zoo and an insect art contest.

CHAMPAIGN, Ill. — After taking an in-depth look at the basic biology of a fungus that is decimating bat colonies as it spreads across the U.S., researchers report that they can find little that might stop the organism from spreading further and persisting indefinitely in bat caves.

Photo by L. Brian Stauffer

Graduate student Daniel Raudabaugh, left, and mycologist Andrew Miller, of the Illinois Natural History Survey, conducted the first in-depth study of the basic biology of P. destructans, the fungus that causes white-nose syndrome in bats.

Their report appears in the journal PLOS ONE.

The aptly named fungus Pseudogymnoascus (Geomyces) destructans causes white-nose syndrome in bats. The infection strikes bats during their winter hibernation, leaving them weakened and susceptible to starvation and secondary infections. The fungus, believed to have originated in Europe, was first seen in New York in the winter of 2006-2007, and now afflicts bats in more than two dozen states. According to the U.S. Fish and Wildlife Service, P. destructans has killed more than 5.5 million bats in the U.S. and Canada.

The fungus thrives at low temperatures, and spreads to bats whose body temperature drops below 20 degrees Celsius (68 degrees Fahrenheit) when they are hibernating in infected caves. Previous research has shown that the fungus persists in caves even after the bats are gone.

The new study, from researchers at the Illinois Natural History Survey at the University of Illinois, found that the fungus can make a meal out of just about any carbon source likely to be found in caves, said graduate student Daniel Raudabaugh, who led the research under the direction of survey mycologist Andrew Miller.

“It can basically live on any complex carbon source, which encompasses insects, undigested insect parts in guano, wood, dead fungi and cave fish,” Raudabaugh said. “We looked at all the different nitrogen sources and found that basically it can grow on all of them. It can grow over a very wide range of pH; it doesn’t have trouble in any pH unless it’s extremely acidic.”

“P. destructans appears to create an environment that should degrade the structure of keratin, the main protein in skin,” Raudabaugh said. It has enzymes that break down urea and proteins that produce a highly alkaline environment that could burn the skin, he said. Infected bats often have holes in their skin, which can increase their susceptibility to other infections.

The fungus can subsist on other proteins and lipids on the bats’ skin, as well as glandular secretions, the researchers said.

“P. destructans can tolerate naturally occurring inhibitory sulfur compounds, and elevated levels of calcium have no effect on fungal growth,” Raudabaugh said.

The only significant limitation of the fungus besides temperatures above 20 degrees Celsius has to do with its ability to take up water, Raudabaugh said. Its cells are leaky, making it hard for the fungus to absorb water from surfaces, such as dry wood, that have a tendency to cling to moisture. But in the presence of degraded fats or free fatty acids, like those found on the skin of living or dead animals, the fungus can draw up water more easily, he said.

“All in all the news for hibernating bats in the U.S. is pretty grim,” Miller said.

“When the fungus first showed up here in Illinois earlier this year we went from zero to 80 percent coverage in a little more than a month,” he said. The team led by U. of I. researchers that discovered the fungus in the state found a single infected bat in one northern Illinois cave, he said. Several weeks later most of the bats in that cave were infected.

Although many studies have been done on the fungal genome and on the bats, Miller said, Raudabaugh is the first to take an in-depth look at the basic biology of the fungus.

“Dan found that P. destructans can live perfectly happily off the remains of most organisms that co-inhabit the caves with the bats,” Miller said. “This means that whether the bats are there or not, it’s going to be in the caves for a very long time.”

The Illinois Natural History Survey is a division of the Prairie Research Institute at the U. of I.

This study was funded through awards given by the Illinois Department of Natural Resources State Wildlife Grants Program (project number T-78-R-1) and the Section 6 Endangered and Threatened Species Program (project number E-54-R-1) to the Illinois Natural History Survey.