Thursday, February 23, 2012

2012 Insect Fear Film Festival promotes fascination with reel ants, real ants

2012 Insect Fear Film Festival promotes fascination with reel ants, real ants

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In anticipation of the 29th Annual Insect Fear Film Festival, which they will host Saturday on the U of I campus, this week’s segment is written and narrated by four members of the Entomology Graduate Student Association: Michelle Duennes, Rob Mitchell, Laura Steele and Andrea Walker.

This year, we’re celebrating international ants and taking a closer look at a few of the remarkable species found around the world.

Two notable groups of ants occur in Central and South America: leaf-cutter ants and bullet ants. Leaf-cutters are known for trimming pieces of leaves, which they bear back to the colony by way of long, meandering trails. There, the leaves are used in vast fungus gardens. The ants feed on this fungus, essentially farming their own food. [Photo of leaf-cutter courtesy of Alex Wild. See more of the coolest insect photos on the Web at alexanderwild.com.]

Less numerous but far more deadly, the bullet ants found in this region of the world are to be appreciated from a safe distance. The sting of a bullet ant is described by stinging insect specialist Jason Schmidt as “pure, intense, brilliant pain. Like fire-walking over flaming charcoal with a 3-inch rusty nail in your heel.”

Of all of the ants, weaver ants of east Asia may possess the most unique nest-building behavior: they weave leaves into homes by using a silk their larvae produce. The adult ant carries the larva in its jaws and rubs it against the edges of leaves to sew them together. These arboreal nests were used in ancient China as the first “biological control” – the nests were connected to citrus trees with ropes, and the ants moved among them and controlled insect pests.

Equally amazing are the trap-jaw ants, which can be found all over the world. These diverse and fearsome insects possess powerful mandibles with a spring-loaded mechanism that inflicts a deadly blow to their prey. They also use their mandibles to catapult themselves into the air, artfully escaping would-be predators.

The last stop on our tour takes us down under to a unique group of ants present around the world but most common in Australia: the Dracula or vampire ants. This ancient group of sightless ants uses elongate mandibles and a harsh sting to paralyze the venomous centipedes. Because adult vampire ants can consume only liquids, they feed these centipedes to the larvae in their colony. Then they earn their name by cutting open the larvae with their mandibles, and draining small quantities of blood, or hemolymph—with minimal harm to the larvae.

Insects are always moving to new parts of the world, usually with some unwitting help from humans, and ants are at the forefront of these invasive species. Managing and preventing the spread of invasive ants and other insects area top priorities of researchers worldwide.

Many people are familiar with red fire ants, which entered the United States through ports and are well known for their ferocious stings. Another species, the Argentine ant, has formed massive supercolonies stretching hundreds of miles in California.

At this year’s Insect Fear Film Festival, we will be showcasing Hollywood’s interpretation of international ants, with films depicting radioactive imported ants in Los Angeles and some South African ants that have taken an unhealthy interest in human skeletons. We’ll contrast these with some live ants on display, including Dinoponera, one of the largest ants in the world.

The Insect Fear Film Festival will take place at the Foellinger Auditorium on the UI campus, with festivities beginning at 6:00 p.m. Further details available at http://www.life.illinois.edu/entomology/egsa/ifff.html

Thursday, February 16, 2012

Cycling made easier by central location

Cycling made easier by central location

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Last Monday morning, for the first time in four and a half years, I bicycled from home to work. The trip was made possible by the fact that my family recently moved back to central Champaign from the very southwest edge of town, where we had bought a house in the summer of 2007.

Back when we were contemplating our move to the suburbs, I convinced myself I would still be able to commute by bike—the ride to campus would just be a little longer.

But there were many impediments to bicycle commuting other than distance, chief among them roadways designed exclusively for cars.

To ride in directly from the southwest, I would have had to cross I-57 on an overpass too narrow for cars to safely get by me, and then travel four miles on Kirby Avenue, which is equally inhospitable to cyclists. On top of that, my children could get nowhere without a ride, so as the parent with the part-time job, I needed access to a car throughout the day.

As a short-term solution to my commuting problem, I bought a campus parking pass and racked up the miles behind the wheel. For a long-term fix, we moved back to the center of town, which brings me again to last Monday morning.

The temperature had dipped into the 20s overnight, so I dug out my cold weather cycling gloves and ear protection. The freezing fog seemed to call for extra visibility, so I donned a safety vest and put new batteries in my blinky lights.

It took me a couple of tries to leave the house. I planned to go without my camera to lighten the load, but when I saw how the fog was frosting the landscape, I turned back for it. What self-respecting photographer could be out on such a day without one?

Halfway down the block again I realized that there was too much breeze blowing through my hair. Home I went for my helmet.

Through downtown Champaign I traveled east on Clark Street and was interested to find bike lanes painted along my route. These particular lanes would do more to promote safe travel were they to include a dashed line at the approach to intersections, as do the other bike lanes established in around town in recent years.

Had I ridden without pause, I could’ve been at my desk in 15 minutes. But life’s a journey, right?

I stopped once to photograph some frost-covered seedpods on a Kentucky coffeetree. And I lingered along the Second Street Basin, where the City of Champaign has done such a fantastic job of combining flood control with the creation of naturalistic open space.

As I approached Scott Park, a Cooper’s hawk lifted off from the native planting along the Boneyard Creek and settled into a nearby tree. While I photographed it, I was struck by how many other cyclists were out, despite the cold and fog. Some zipped by on Springfield Avenue integrated with the flow of car traffic, while others meandered through the park like me.

My observation seemed to confirm what I read recently, that increasing numbers of Champaign-Urbana residents are making more trips by means other than car. That’s a trend I’m delighted to participate in.

Thursday, February 09, 2012

Bicentennial of New Madrid earthquakes raises question of hazard today

Bicentennial of New Madrid earthquakes raises question of hazard today

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Two hundred years ago this week, a powerful earthquake shook the Mississippi Valley near the southern tip of Illinois. It was the fourth in a series of quakes that punctuated months of heightened seismic activity stretching back to the preceding December.

In New Madrid, the Missouri settlement that gave the quakes a name, homes that had survived the previous shocks were thrown down, and sand and water spewed from fissures in the earth, covering hundreds of acres.

Nearby, the Mississippi River receded from its banks and then swelled with the force of a tsunami. Waterfalls sprang up where the fault crossed the stream, and the current of the great river seemed to run backward for a time.

[Images: Nineteenth century woodcut depicting effects of the earthquake (source to be determined); most recent USGS earthquake hazard map for 48 coterminous states from http://earthquake.usgs.gov/hazards/products/]

Despite the enormous power of the New Madrid earthquakes, there is no certain evidence that anyone died in them. At the time, the region was lightly populated, and it had few of the human structures that suffer damage when the ground shakes.

According Steve Marshak, a professor of geology who directs the School of Earth, Society, and Environment at the U of I, the New Madrid quakes were unusual in that they occurred along a line of faults in the interior of a single tectonic plate, rather than along a boundary where plates come together, which is where the great majority of quakes occur.

From a distance of 200 years, and secure in the knowledge that no lives were lost, reading the widely-available firsthand accounts of the New Madrid quakes can provide the same pleasure as watching a disaster movie. But were earthquakes of similar magnitude to occur today, the human consequences could be devastating.

The cities of St. Louis and Memphis both lie close enough to the New Madrid seismic zone to experience significant effects from a major earthquake centered there. Because of that, a great deal of scientific effort continues to go into estimating the probability of such an event.

Some scientists, especially at the U.S. Geological Survey, estimate the annual probability of a major New Madrid quake to be quite high. In fact, the 1996 update of the USGS earthquake hazard map puts earthquake hazard in the New Madrid area higher than the hazard in California.

Others, most notably Seth Stein, a professor of geology at Northwestern University, argue that the earthquake hazard in the New Madrid area is probably much lower. Stein makes this case in a lively 2010 book addressed to nonscientists called “Disaster Deferred: How New Science Is Changing Our View of Earthquake Hazards in the Midwest.”

Stein bases his argument in part on the fact that extremely precise measurements taken over the last twenty years show that the ground across the faults in the New Madrid zone is moving less than 2 millimeters per year. In contrast, he notes, the ground across the San Andreas Fault in California—where big earthquakes occur about every hundred years—moves about 36 millimeters per year.

Stein also provides extensive explanations of how seismologists estimate earthquake hazards, and a thorough critique of the methods and assumptions that account for the high hazard levels USGS assigns the New Madrid area.

All of this matters, of course, because constructing new buildings and retrofitting old ones to California standards costs a lot of money, money that would be better spent elsewhere if large New Madrid quakes are unlikely in the foreseeable future.

Thursday, February 02, 2012

Equinox House a powerful example of conservation in Urbana

Equinox House a powerful example of conservation in Urbana

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How much fossil fuel does it take to operate a comfortable home for a couple of retired American baby-boomers?

None.

That’s the straight answer from Ty and Deb Newell of Urbana. And they hope the example of their home, the “Equinox House,” will awaken others to the opportunity of constructing a net-zero energy house in the Midwest using technology available today.

The Newells recently celebrated the first anniversary of life in the “Equinox House,” so there’s more than a year’s worth of data about how much electricity they used on day-to-day basis, as well as how much electricity their solar panels produced.

According to Ty Newell, who is professor emeritus of mechanical engineering at the UI, the Equinox House required about 12,000 kilowatt-hours of electricity to operate during the December 2010 through November 2011 period. That total includes everything from heating and air conditioning, to hot water heat, clothes washing and drying, and all other appliances. (No natural gas is used in the house.)

Newell noted that energy use in the Equinox House for the first year was approximately 20 percent greater than it will be in this and subsequent years. That’s because he was using the least efficient of three different heating systems that will be tested in the home.

During the first year, the solar panels that power the Equinox House produced approximately 11,000 kilowatt-hours of electricity. This would have made the Newells purchasers of 1,000 kilowatt-hours, in net terms, had it not been for the fact that the solar panels were on line for some time before they moved into the house.

Thanks to the more efficient heating system now in place, the Equinox House will produce surplus electricity this year and in the future. That’s by design. The “extra” will be used to power an electric vehicle, which the Newells intend to purchase as one becomes available this year.

In conjunction with its solar panels, the Equinox House achieves net-zero energy use because it requires far less energy than even a well-built conventional home—about one-fifth as much. And it does so through the use of design and technology that did not add a significant burden to the cost of construction.

When he talks about the Equinox House, Ty Newell emphasizes how well it works from an economic perspective, since the couple’s average daily cost for energy is a mere $3.00. That’s based on a twenty-year life for the solar array, which cost a net of $20,000 installed.

In addition, Newell enjoys the fact that a significant part of their up-front expenditure supported job creation, the labor that went into the manufacture and installation of their solar panels. That’s in contrast to money they might have otherwise spent on fossil fuel.

You might think that the Newells must be sacrificing comfort for the sake of energy savings, but that’s not the case. Their house boasts 2,100 square feet of living space and all of the amenities you would expect in a contemporary suburban development.

On top of that, they enjoy much better indoor air quality than those of us who live in conventional homes, thanks to a constant flow of conditioned fresh air from the outside.